diff --git a/src/Base/Parameter.cpp b/src/Base/Parameter.cpp
index bfab1492fb..046e516d15 100644
--- a/src/Base/Parameter.cpp
+++ b/src/Base/Parameter.cpp
@@ -81,7 +81,7 @@ using namespace Base;
 
 //**************************************************************************
 //**************************************************************************
-// privat classes declaration:
+// private classes declaration:
 // - DOMTreeErrorReporter
 // - StrX
 // - DOMPrintFilter
@@ -195,12 +195,12 @@ class DOMPrintErrorHandler : public DOMErrorHandler
 {
 public:
 
-    DOMPrintErrorHandler() {};
-    ~DOMPrintErrorHandler() {};
+    DOMPrintErrorHandler() {}
+    ~DOMPrintErrorHandler() {}
 
     /** @name The error handler interface */
     bool handleError(const DOMError& domError);
-    void resetErrors() {};
+    void resetErrors() {}
 
 private :
     /* Unimplemented constructors and operators */
@@ -391,10 +391,10 @@ std::vector<Base::Reference<ParameterGrp> > ParameterGrp::GetGroups(void)
     pcTemp = FindElement(_pGroupNode,"FCParamGroup");
 
     while (pcTemp) {
-        Name = StrX( ((DOMElement*)pcTemp)->getAttributes()->getNamedItem(XStr("Name").unicodeForm())->getNodeValue()).c_str();
+        Name = StrX(static_cast<DOMElement*>(pcTemp)->getAttributes()->getNamedItem(XStr("Name").unicodeForm())->getNodeValue()).c_str();
         // already created?
         if (!(rParamGrp=_GroupMap[Name]).isValid()) {
-            rParamGrp = Base::Reference<ParameterGrp> (new ParameterGrp(((DOMElement*)pcTemp),Name.c_str()));
+            rParamGrp = Base::Reference<ParameterGrp> (new ParameterGrp(static_cast<DOMElement*>(pcTemp),Name.c_str()));
             _GroupMap[Name] = rParamGrp;
         }
         vrParamGrp.push_back( rParamGrp );
@@ -443,10 +443,12 @@ void  ParameterGrp::SetBool(const char* Name, bool bValue)
 {
     // find or create the Element
     DOMElement *pcElem = FindOrCreateElement(_pGroupNode,"FCBool",Name);
-    // and set the value
-    pcElem->setAttribute(XStr("Value").unicodeForm(), XStr(bValue?"1":"0").unicodeForm());
-    // trigger observer
-    Notify(Name);
+    if (pcElem) {
+        // and set the value
+        pcElem->setAttribute(XStr("Value").unicodeForm(), XStr(bValue?"1":"0").unicodeForm());
+        // trigger observer
+        Notify(Name);
+    }
 }
 
 std::vector<bool> ParameterGrp::GetBools(const char * sFilter) const
@@ -457,10 +459,10 @@ std::vector<bool> ParameterGrp::GetBools(const char * sFilter) const
 
     pcTemp = FindElement(_pGroupNode,"FCBool");
     while ( pcTemp) {
-        Name = StrX( ((DOMElement*)pcTemp)->getAttributes()->getNamedItem(XStr("Name").unicodeForm())->getNodeValue()).c_str();
+        Name = StrX(static_cast<DOMElement*>(pcTemp)->getAttributes()->getNamedItem(XStr("Name").unicodeForm())->getNodeValue()).c_str();
         // check on filter condition
         if (sFilter == NULL || Name.find(sFilter)!= std::string::npos) {
-            if (strcmp(StrX(((DOMElement*)pcTemp)->getAttribute(XStr("Value").unicodeForm())).c_str(),"1"))
+            if (strcmp(StrX(static_cast<DOMElement*>(pcTemp)->getAttribute(XStr("Value").unicodeForm())).c_str(),"1"))
                 vrValues.push_back(false);
             else
                 vrValues.push_back(true);
@@ -479,10 +481,10 @@ std::vector<std::pair<std::string,bool> > ParameterGrp::GetBoolMap(const char *
 
     pcTemp = FindElement(_pGroupNode,"FCBool");
     while ( pcTemp) {
-        Name = StrX( ((DOMElement*)pcTemp)->getAttributes()->getNamedItem(XStr("Name").unicodeForm())->getNodeValue()).c_str();
+        Name = StrX(static_cast<DOMElement*>(pcTemp)->getAttributes()->getNamedItem(XStr("Name").unicodeForm())->getNodeValue()).c_str();
         // check on filter condition
         if (sFilter == NULL || Name.find(sFilter)!= std::string::npos) {
-            if (strcmp(StrX(((DOMElement*)pcTemp)->getAttribute(XStr("Value").unicodeForm())).c_str(),"1"))
+            if (strcmp(StrX(static_cast<DOMElement*>(pcTemp)->getAttribute(XStr("Value").unicodeForm())).c_str(),"1"))
                 vrValues.push_back(std::make_pair(Name, false));
             else
                 vrValues.push_back(std::make_pair(Name, true));
@@ -508,11 +510,13 @@ void  ParameterGrp::SetInt(const char* Name, long lValue)
     char cBuf[256];
     // find or create the Element
     DOMElement *pcElem = FindOrCreateElement(_pGroupNode,"FCInt",Name);
-    // and set the value
-    sprintf(cBuf,"%li",lValue);
-    pcElem->setAttribute(XStr("Value").unicodeForm(), XStr(cBuf).unicodeForm());
-    // trigger observer
-    Notify(Name);
+    if (pcElem) {
+        // and set the value
+        sprintf(cBuf,"%li",lValue);
+        pcElem->setAttribute(XStr("Value").unicodeForm(), XStr(cBuf).unicodeForm());
+        // trigger observer
+        Notify(Name);
+    }
 }
 
 std::vector<long> ParameterGrp::GetInts(const char * sFilter) const
@@ -523,10 +527,10 @@ std::vector<long> ParameterGrp::GetInts(const char * sFilter) const
 
     pcTemp = FindElement(_pGroupNode,"FCInt") ;
     while ( pcTemp ) {
-        Name = StrX( ((DOMElement*)pcTemp)->getAttributes()->getNamedItem(XStr("Name").unicodeForm())->getNodeValue()).c_str();
+        Name = StrX(static_cast<DOMElement*>(pcTemp)->getAttributes()->getNamedItem(XStr("Name").unicodeForm())->getNodeValue()).c_str();
         // check on filter condition
         if (sFilter == NULL || Name.find(sFilter)!= std::string::npos) {
-            vrValues.push_back( atol (StrX(((DOMElement*)pcTemp)->getAttribute(XStr("Value").unicodeForm())).c_str()) );
+            vrValues.push_back(atol(StrX(static_cast<DOMElement*>(pcTemp)->getAttribute(XStr("Value").unicodeForm())).c_str()) );
         }
         pcTemp = FindNextElement(pcTemp,"FCInt") ;
     }
@@ -542,11 +546,11 @@ std::vector<std::pair<std::string,long> > ParameterGrp::GetIntMap(const char * s
 
     pcTemp = FindElement(_pGroupNode,"FCInt") ;
     while ( pcTemp ) {
-        Name = StrX( ((DOMElement*)pcTemp)->getAttributes()->getNamedItem(XStr("Name").unicodeForm())->getNodeValue()).c_str();
+        Name = StrX(static_cast<DOMElement*>(pcTemp)->getAttributes()->getNamedItem(XStr("Name").unicodeForm())->getNodeValue()).c_str();
         // check on filter condition
         if (sFilter == NULL || Name.find(sFilter)!= std::string::npos) {
             vrValues.push_back(std::make_pair(Name,
-                               ( atol (StrX(((DOMElement*)pcTemp)->getAttribute(XStr("Value").unicodeForm())).c_str()))));
+                               ( atol (StrX(static_cast<DOMElement*>(pcTemp)->getAttribute(XStr("Value").unicodeForm())).c_str()))));
         }
         pcTemp = FindNextElement(pcTemp,"FCInt") ;
     }
@@ -569,11 +573,13 @@ void  ParameterGrp::SetUnsigned(const char* Name, unsigned long lValue)
     char cBuf[256];
     // find or create the Element
     DOMElement *pcElem = FindOrCreateElement(_pGroupNode,"FCUInt",Name);
-    // and set the value
-    sprintf(cBuf,"%lu",lValue);
-    pcElem->setAttribute(XStr("Value").unicodeForm(), XStr(cBuf).unicodeForm());
-    // trigger observer
-    Notify(Name);
+    if (pcElem) {
+        // and set the value
+        sprintf(cBuf,"%lu",lValue);
+        pcElem->setAttribute(XStr("Value").unicodeForm(), XStr(cBuf).unicodeForm());
+        // trigger observer
+        Notify(Name);
+    }
 }
 
 std::vector<unsigned long> ParameterGrp::GetUnsigneds(const char * sFilter) const
@@ -584,10 +590,10 @@ std::vector<unsigned long> ParameterGrp::GetUnsigneds(const char * sFilter) cons
 
     pcTemp = FindElement(_pGroupNode,"FCUInt");
     while ( pcTemp ) {
-        Name = StrX( ((DOMElement*)pcTemp)->getAttributes()->getNamedItem(XStr("Name").unicodeForm())->getNodeValue()).c_str();
+        Name = StrX(static_cast<DOMElement*>(pcTemp)->getAttributes()->getNamedItem(XStr("Name").unicodeForm())->getNodeValue()).c_str();
         // check on filter condition
         if (sFilter == NULL || Name.find(sFilter)!= std::string::npos) {
-            vrValues.push_back( strtoul (StrX(((DOMElement*)pcTemp)->getAttribute(XStr("Value").unicodeForm())).c_str(),0,10) );
+            vrValues.push_back( strtoul (StrX(static_cast<DOMElement*>(pcTemp)->getAttribute(XStr("Value").unicodeForm())).c_str(),0,10) );
         }
         pcTemp = FindNextElement(pcTemp,"FCUInt") ;
     }
@@ -603,11 +609,11 @@ std::vector<std::pair<std::string,unsigned long> > ParameterGrp::GetUnsignedMap(
 
     pcTemp = FindElement(_pGroupNode,"FCUInt");
     while ( pcTemp ) {
-        Name = StrX( ((DOMElement*)pcTemp)->getAttributes()->getNamedItem(XStr("Name").unicodeForm())->getNodeValue()).c_str();
+        Name = StrX(static_cast<DOMElement*>(pcTemp)->getAttributes()->getNamedItem(XStr("Name").unicodeForm())->getNodeValue()).c_str();
         // check on filter condition
         if (sFilter == NULL || Name.find(sFilter)!= std::string::npos) {
             vrValues.push_back(std::make_pair(Name,
-                               ( strtoul (StrX(((DOMElement*)pcTemp)->getAttribute(XStr("Value").unicodeForm())).c_str(),0,10) )));
+                               ( strtoul (StrX(static_cast<DOMElement*>(pcTemp)->getAttribute(XStr("Value").unicodeForm())).c_str(),0,10) )));
         }
         pcTemp = FindNextElement(pcTemp,"FCUInt");
     }
@@ -630,11 +636,13 @@ void  ParameterGrp::SetFloat(const char* Name, double dValue)
     char cBuf[256];
     // find or create the Element
     DOMElement *pcElem = FindOrCreateElement(_pGroupNode,"FCFloat",Name);
-    // and set the value
-    sprintf(cBuf,"%.12f",dValue); // use %.12f instead of %f to handle values < 1.0e-6
-    pcElem->setAttribute(XStr("Value").unicodeForm(), XStr(cBuf).unicodeForm());
-    // trigger observer
-    Notify(Name);
+    if (pcElem) {
+        // and set the value
+        sprintf(cBuf,"%.12f",dValue); // use %.12f instead of %f to handle values < 1.0e-6
+        pcElem->setAttribute(XStr("Value").unicodeForm(), XStr(cBuf).unicodeForm());
+        // trigger observer
+        Notify(Name);
+    }
 }
 
 std::vector<double> ParameterGrp::GetFloats(const char * sFilter) const
@@ -645,10 +653,10 @@ std::vector<double> ParameterGrp::GetFloats(const char * sFilter) const
 
     pcTemp = FindElement(_pGroupNode,"FCFloat") ;
     while ( pcTemp ) {
-        Name = StrX( ((DOMElement*)pcTemp)->getAttributes()->getNamedItem(XStr("Name").unicodeForm())->getNodeValue()).c_str();
+        Name = StrX(static_cast<DOMElement*>(pcTemp)->getAttributes()->getNamedItem(XStr("Name").unicodeForm())->getNodeValue()).c_str();
         // check on filter condition
         if (sFilter == NULL || Name.find(sFilter)!= std::string::npos) {
-            vrValues.push_back( atof (StrX(((DOMElement*)pcTemp)->getAttribute(XStr("Value").unicodeForm())).c_str()) );
+            vrValues.push_back( atof (StrX(static_cast<DOMElement*>(pcTemp)->getAttribute(XStr("Value").unicodeForm())).c_str()) );
         }
         pcTemp = FindNextElement(pcTemp,"FCFloat");
     }
@@ -664,11 +672,11 @@ std::vector<std::pair<std::string,double> > ParameterGrp::GetFloatMap(const char
 
     pcTemp = FindElement(_pGroupNode,"FCFloat") ;
     while ( pcTemp ) {
-        Name = StrX( ((DOMElement*)pcTemp)->getAttributes()->getNamedItem(XStr("Name").unicodeForm())->getNodeValue()).c_str();
+        Name = StrX(static_cast<DOMElement*>(pcTemp)->getAttributes()->getNamedItem(XStr("Name").unicodeForm())->getNodeValue()).c_str();
         // check on filter condition
         if (sFilter == NULL || Name.find(sFilter)!= std::string::npos) {
             vrValues.push_back(std::make_pair(Name,
-                               ( atof (StrX(((DOMElement*)pcTemp)->getAttribute(XStr("Value").unicodeForm())).c_str()))));
+                               ( atof (StrX(static_cast<DOMElement*>(pcTemp)->getAttribute(XStr("Value").unicodeForm())).c_str()))));
         }
         pcTemp = FindNextElement(pcTemp,"FCFloat");
     }
@@ -694,19 +702,20 @@ void  ParameterGrp::SetASCII(const char* Name, const char *sValue)
 {
     // find or create the Element
     DOMElement *pcElem = FindOrCreateElement(_pGroupNode,"FCText",Name);
-    // and set the value
-    DOMNode *pcElem2 = pcElem->getFirstChild();
-    if (!pcElem2) {
-        XERCES_CPP_NAMESPACE_QUALIFIER DOMDocument *pDocument = _pGroupNode->getOwnerDocument();
-        DOMText *pText = pDocument->createTextNode(XUTF8Str(sValue).unicodeForm());
-        pcElem->appendChild(pText);
+    if (pcElem) {
+        // and set the value
+        DOMNode *pcElem2 = pcElem->getFirstChild();
+        if (!pcElem2) {
+            XERCES_CPP_NAMESPACE_QUALIFIER DOMDocument *pDocument = _pGroupNode->getOwnerDocument();
+            DOMText *pText = pDocument->createTextNode(XUTF8Str(sValue).unicodeForm());
+            pcElem->appendChild(pText);
+        }
+        else {
+            pcElem2->setNodeValue(XUTF8Str(sValue).unicodeForm());
+        }
+        // trigger observer
+        Notify(Name);
     }
-    else {
-        pcElem2->setNodeValue(XUTF8Str(sValue).unicodeForm());
-    }
-    // trigger observer
-    Notify(Name);
-
 }
 
 std::string ParameterGrp::GetASCII(const char* Name, const char * pPreset) const
@@ -739,7 +748,7 @@ std::vector<std::string> ParameterGrp::GetASCIIs(const char * sFilter) const
 
     pcTemp = FindElement(_pGroupNode,"FCText");
     while ( pcTemp  ) {
-        Name = StrXUTF8( ((DOMElement*)pcTemp)->getAttributes()->getNamedItem(XStr("Name").unicodeForm())->getNodeValue()).c_str();
+        Name = StrXUTF8(static_cast<DOMElement*>(pcTemp)->getAttributes()->getNamedItem(XStr("Name").unicodeForm())->getNodeValue()).c_str();
         // check on filter condition
         if (sFilter == NULL || Name.find(sFilter)!= std::string::npos) {
             // retrieve the text element
@@ -761,7 +770,7 @@ std::vector<std::pair<std::string,std::string> > ParameterGrp::GetASCIIMap(const
 
     pcTemp = FindElement(_pGroupNode,"FCText");
     while ( pcTemp) {
-        Name = StrXUTF8( ((DOMElement*)pcTemp)->getAttributes()->getNamedItem(XStr("Name").unicodeForm())->getNodeValue()).c_str();
+        Name = StrXUTF8(static_cast<DOMElement*>(pcTemp)->getAttributes()->getNamedItem(XStr("Name").unicodeForm())->getNodeValue()).c_str();
         // check on filter condition
         if (sFilter == NULL || Name.find(sFilter)!= std::string::npos) {
             // retrieve the text element
@@ -778,22 +787,6 @@ std::vector<std::pair<std::string,std::string> > ParameterGrp::GetASCIIMap(const
 //**************************************************************************
 // Access methods
 
-void ParameterGrp::RemoveGrp(const char* Name)
-{
-    // remove group handle
-    _GroupMap.erase(Name);
-
-    // check if Element in group
-    DOMElement *pcElem = FindElement(_pGroupNode,"FCParamGroup",Name);
-    // if not return
-    if (!pcElem)
-        return;
-    else
-        _pGroupNode->removeChild(pcElem);
-    // trigger observer
-    Notify(Name);
-}
-
 void ParameterGrp::RemoveASCII(const char* Name)
 {
     // check if Element in group
@@ -801,11 +794,12 @@ void ParameterGrp::RemoveASCII(const char* Name)
     // if not return
     if (!pcElem)
         return;
-    else
-        _pGroupNode->removeChild(pcElem);
+
+    DOMNode* node = _pGroupNode->removeChild(pcElem);
+    node->release();
+
     // trigger observer
     Notify(Name);
-
 }
 
 void ParameterGrp::RemoveBool(const char* Name)
@@ -815,8 +809,9 @@ void ParameterGrp::RemoveBool(const char* Name)
     // if not return
     if (!pcElem)
         return;
-    else
-        _pGroupNode->removeChild(pcElem);
+
+    DOMNode* node = _pGroupNode->removeChild(pcElem);
+    node->release();
 
     // trigger observer
     Notify(Name);
@@ -842,8 +837,9 @@ void ParameterGrp::RemoveFloat(const char* Name)
     // if not return
     if (!pcElem)
         return;
-    else
-        _pGroupNode->removeChild(pcElem);
+
+    DOMNode* node = _pGroupNode->removeChild(pcElem);
+    node->release();
 
     // trigger observer
     Notify(Name);
@@ -856,8 +852,9 @@ void ParameterGrp::RemoveInt(const char* Name)
     // if not return
     if (!pcElem)
         return;
-    else
-        _pGroupNode->removeChild(pcElem);
+
+    DOMNode* node = _pGroupNode->removeChild(pcElem);
+    node->release();
 
     // trigger observer
     Notify(Name);
@@ -870,8 +867,38 @@ void ParameterGrp::RemoveUnsigned(const char* Name)
     // if not return
     if (!pcElem)
         return;
-    else
-        _pGroupNode->removeChild(pcElem);
+
+    DOMNode* node = _pGroupNode->removeChild(pcElem);
+    node->release();
+
+    // trigger observer
+    Notify(Name);
+}
+
+void ParameterGrp::RemoveGrp(const char* Name)
+{
+    auto it = _GroupMap.find(Name);
+    if (it == _GroupMap.end())
+        return;
+
+    // if this or any of its children is referenced by an observer
+    // it cannot be deleted
+    if (!it->second->ShouldRemove()) {
+        it->second->Clear();
+    }
+    else {
+        // check if Element in group
+        DOMElement *pcElem = FindElement(_pGroupNode,"FCParamGroup",Name);
+        // if not return
+        if (!pcElem)
+            return;
+
+        // remove group handle
+        _GroupMap.erase(Name);
+
+        DOMNode* node = _pGroupNode->removeChild(pcElem);
+        node->release();
+    }
 
     // trigger observer
     Notify(Name);
@@ -882,34 +909,63 @@ void ParameterGrp::Clear(void)
     std::vector<DOMNode*> vecNodes;
 
     // checking on references
-    std::map <std::string ,Base::Reference<ParameterGrp> >::iterator It1;
-    for (It1 = _GroupMap.begin();It1!=_GroupMap.end();++It1)
-        if (It1->second.getRefCount() > 1)
-            Console().Warning("ParameterGrp::Clear(): Group clear with active references");
-    // remove group handles
-    _GroupMap.clear();
+    std::vector<std::string> removeGrp;
+    for (auto it = _GroupMap.begin();it!=_GroupMap.end();++it) {
+        // If a group is referenced by some observer then do not remove it
+        // but clear it
+        if (!it->second->ShouldRemove()) {
+            it->second->Clear();
+        }
+        else {
+            removeGrp.push_back(it->first);
+        }
+    }
 
-    // searching all nodes
-    for (DOMNode *clChild = _pGroupNode->getFirstChild(); clChild != 0;  clChild = clChild->getNextSibling()) {
-        vecNodes.push_back(clChild);
+    // remove group handles
+    for (auto it : removeGrp) {
+        auto pos = _GroupMap.find(it);
+        vecNodes.push_back(pos->second->_pGroupNode);
+        _GroupMap.erase(pos->first);
+    }
+
+    // searching all non-group nodes
+    for (DOMNode *child = _pGroupNode->getFirstChild(); child != 0;  child = child->getNextSibling()) {
+        if (XMLString::compareString(child->getNodeName(), XStr("FCParamGroup").unicodeForm()) != 0)
+            vecNodes.push_back(child);
     }
 
     // deleting the nodes
-    DOMNode* pcTemp;
-    for (std::vector<DOMNode*>::iterator It=vecNodes.begin();It!=vecNodes.end();++It) {
-        pcTemp = _pGroupNode->removeChild(*It);
-        //delete pcTemp;
-        pcTemp->release();
+    for (auto it = vecNodes.begin(); it != vecNodes.end(); ++it) {
+        DOMNode *child = _pGroupNode->removeChild(*it);
+        child->release();
     }
+
     // trigger observer
-    Notify(0);
+    Notify("");
 }
 
 //**************************************************************************
 // Access methods
 
+bool ParameterGrp::ShouldRemove() const
+{
+    if (this->getRefCount() > 1)
+        return false;
+    for (auto it : _GroupMap) {
+        bool ok = it.second->ShouldRemove();
+        if (!ok)
+            return false;
+    }
+    return true;
+}
+
 XERCES_CPP_NAMESPACE_QUALIFIER DOMElement *ParameterGrp::FindElement(XERCES_CPP_NAMESPACE_QUALIFIER DOMElement *Start, const char* Type, const char* Name) const
 {
+    if (XMLString::compareString(Start->getNodeName(), XStr("FCParamGroup").unicodeForm()) != 0 &&
+        XMLString::compareString(Start->getNodeName(), XStr("FCParameters").unicodeForm()) != 0) {
+        Base::Console().Warning("FindElement: %s cannot have the element %s of type %s\n", StrX(Start->getNodeName()).c_str(), Name, Type);
+        return nullptr;
+    }
     for (DOMNode *clChild = Start->getFirstChild(); clChild != 0;  clChild = clChild->getNextSibling()) {
         if (clChild->getNodeType() == DOMNode::ELEMENT_NODE) {
             // the right node Type
@@ -917,10 +973,10 @@ XERCES_CPP_NAMESPACE_QUALIFIER DOMElement *ParameterGrp::FindElement(XERCES_CPP_
                 if (clChild->getAttributes()->getLength() > 0) {
                     if (Name) {
                         if (!strcmp(Name,StrX(clChild->getAttributes()->getNamedItem(XStr("Name").unicodeForm())->getNodeValue()).c_str()))
-                            return (DOMElement*)clChild;
+                            return static_cast<DOMElement*>(clChild);
                     }
                     else
-                        return (DOMElement*)clChild;
+                        return static_cast<DOMElement*>(clChild);
 
                 }
             }
@@ -932,13 +988,14 @@ XERCES_CPP_NAMESPACE_QUALIFIER DOMElement *ParameterGrp::FindElement(XERCES_CPP_
 XERCES_CPP_NAMESPACE_QUALIFIER DOMElement *ParameterGrp::FindNextElement(XERCES_CPP_NAMESPACE_QUALIFIER DOMNode *Prev, const char* Type) const
 {
     DOMNode *clChild = Prev;
-    if (!clChild) return 0l;
+    if (!clChild)
+        return nullptr;
 
     while ((clChild = clChild->getNextSibling())!=0) {
         if (clChild->getNodeType() == DOMNode::ELEMENT_NODE) {
             // the right node Type
             if (!strcmp(Type,StrX(clChild->getNodeName()).c_str())) {
-                return (DOMElement*)clChild;
+                return static_cast<DOMElement*>(clChild);
             }
         }
     }
@@ -949,15 +1006,21 @@ XERCES_CPP_NAMESPACE_QUALIFIER DOMElement *ParameterGrp::FindOrCreateElement(XER
 {
     // first try to find it
     DOMElement *pcElem = FindElement(Start,Type,Name);
+    if (pcElem)
+        return pcElem;
 
-    if (!pcElem) {
-        XERCES_CPP_NAMESPACE_QUALIFIER DOMDocument *pDocument = _pGroupNode->getOwnerDocument();
-
-        pcElem = pDocument->createElement(XStr(Type).unicodeForm());
-        pcElem-> setAttribute(XStr("Name").unicodeForm(), XStr(Name).unicodeForm());
-        Start->appendChild(pcElem);
+    if (XMLString::compareString(Start->getNodeName(), XStr("FCParamGroup").unicodeForm()) != 0 &&
+        XMLString::compareString(Start->getNodeName(), XStr("FCParameters").unicodeForm()) != 0) {
+        Base::Console().Warning("FindOrCreateElement: %s cannot have the element %s of type %s\n", StrX(Start->getNodeName()).c_str(), Name, Type);
+        return nullptr;
     }
 
+    XERCES_CPP_NAMESPACE_QUALIFIER DOMDocument *pDocument = _pGroupNode->getOwnerDocument();
+
+    pcElem = pDocument->createElement(XStr(Type).unicodeForm());
+    pcElem-> setAttribute(XStr("Name").unicodeForm(), XStr(Name).unicodeForm());
+    Start->appendChild(pcElem);
+
     return pcElem;
 }
 
@@ -1189,7 +1252,7 @@ int  ParameterManager::LoadDocument(const char* sFileName)
 
     try {
 #if defined (FC_OS_WIN32)
-        LocalFileInputSource inputSource((XMLCh*)file.toStdWString().c_str());
+        LocalFileInputSource inputSource(reinterpret_cast<const XMLCh*>(file.toStdWString().c_str()));
 #else
         LocalFileInputSource inputSource(XStr(file.filePath().c_str()).unicodeForm());
 #endif
@@ -1286,7 +1349,7 @@ void  ParameterManager::SaveDocument(const char* sFileName) const
         // to a file once it receives any thing from the serializer.
         //
 #if defined (FC_OS_WIN32)
-        XMLFormatTarget *myFormTarget = new LocalFileFormatTarget ((XMLCh*)file.toStdWString().c_str());
+        XMLFormatTarget *myFormTarget = new LocalFileFormatTarget (reinterpret_cast<const XMLCh*>(file.toStdWString().c_str()));
 #else
         XMLFormatTarget *myFormTarget = new LocalFileFormatTarget (file.filePath().c_str());
 #endif
@@ -1378,7 +1441,7 @@ void  ParameterManager::SaveDocument(XMLFormatTarget* pFormatTarget) const
         XMLCh tempStr[100];
         XMLString::transcode("LS", tempStr, 99);
         DOMImplementation *impl          = DOMImplementationRegistry::getDOMImplementation(tempStr);
-        DOMLSSerializer   *theSerializer = ((DOMImplementationLS*)impl)->createLSSerializer();
+        DOMLSSerializer   *theSerializer = static_cast<DOMImplementationLS*>(impl)->createLSSerializer();
 
         // set user specified end of line sequence and output encoding
         theSerializer->setNewLine(gMyEOLSequence);
@@ -1388,7 +1451,7 @@ void  ParameterManager::SaveDocument(XMLFormatTarget* pFormatTarget) const
         // do the serialization through DOMWriter::writeNode();
         //
         if (_pDocument) {
-            DOMLSOutput *theOutput = ((DOMImplementationLS*)impl)->createLSOutput();
+            DOMLSOutput *theOutput = static_cast<DOMImplementationLS*>(impl)->createLSOutput();
             theOutput->setEncoding(gOutputEncoding);
 
             if (gUseFilter) {
@@ -1443,7 +1506,7 @@ void  ParameterManager::CreateDocument(void)
     // creating the node for the root group
     DOMElement* rootElem = _pDocument->getDocumentElement();
     _pGroupNode = _pDocument->createElement(XStr("FCParamGroup").unicodeForm());
-    ((DOMElement*)_pGroupNode)->setAttribute(XStr("Name").unicodeForm(), XStr("Root").unicodeForm());
+    static_cast<DOMElement*>(_pGroupNode)->setAttribute(XStr("Name").unicodeForm(), XStr("Root").unicodeForm());
     rootElem->appendChild(_pGroupNode);
 }
 
diff --git a/src/Base/Parameter.h b/src/Base/Parameter.h
index 081580a918..7a7b7ee67a 100644
--- a/src/Base/Parameter.h
+++ b/src/Base/Parameter.h
@@ -22,6 +22,13 @@
  *   Juergen Riegel 2002                                                   *
  ***************************************************************************/
 
+ /** 
+ * \file Parameter.h
+ * \brief The classes defined here are used to interface with the XML-based
+ * FreeCAD config files: user.cfg and system.cfg files. It can parse, get,
+ * and store the parameters/configurations for the user's preferences.
+ * 3rd party Xerces-C++ XML parser is used to parse and write the XML.
+ */
 
 #ifndef BASE__PARAMETER_H
 #define BASE__PARAMETER_H
@@ -93,7 +100,7 @@ class ParameterManager;
  *  kind of preferences and so on.
  *  @see ParameterManager
  */
-class  BaseExport ParameterGrp	: public Base::Handled,public Base::Subject <const char*>
+class  BaseExport ParameterGrp : public Base::Handled,public Base::Subject <const char*>
 {
 
 
@@ -236,6 +243,7 @@ protected:
     ~ParameterGrp();
     /// helper function for GetGroup
     Base::Reference<ParameterGrp> _GetGroup(const char* Name);
+    bool ShouldRemove() const;
 
     XERCES_CPP_NAMESPACE_QUALIFIER DOMElement *FindNextElement(XERCES_CPP_NAMESPACE_QUALIFIER DOMNode *Prev, const char* Type) const;
 
diff --git a/src/Base/swigpyrun.inl b/src/Base/swigpyrun.inl
index 0eedaaa87a..65bba62db3 100644
--- a/src/Base/swigpyrun.inl
+++ b/src/Base/swigpyrun.inl
@@ -72,7 +72,7 @@ void cleanupSWIG_T(const char* TypeName)
 
     PyObject *module, *dict;
     PyInterpreterState *interp = PyThreadState_GET()->interp;
-    PyObject *modules = interp->modules;
+    PyObject *modules = PyImport_GetModuleDict();
     module = PyDict_GetItemString(modules, "__builtin__");
     if (module != NULL && PyModule_Check(module)) {
         dict = PyModule_GetDict(module);
diff --git a/src/Gui/DlgParameterImp.cpp b/src/Gui/DlgParameterImp.cpp
index eb09ecc2e7..61c7fd9048 100644
--- a/src/Gui/DlgParameterImp.cpp
+++ b/src/Gui/DlgParameterImp.cpp
@@ -404,16 +404,21 @@ void ParameterGroup::onDeleteSelectedItem()
     QTreeWidgetItem* sel = currentItem();
     if (isItemSelected(sel) && sel->parent())
     {
-        if ( QMessageBox::question(this, tr("Remove group"), tr("Do really want to remove this parameter group?"),
+        if ( QMessageBox::question(this, tr("Remove group"), tr("Do you really want to remove this parameter group?"),
                                QMessageBox::Yes, QMessageBox::No|QMessageBox::Default|QMessageBox::Escape) == 
                                QMessageBox::Yes )
         {
             QTreeWidgetItem* parent = sel->parent();
             int index = parent->indexOfChild(sel);
             parent->takeChild(index);
-            ParameterGroupItem* para = static_cast<ParameterGroupItem*>(parent);
-            para->_hcGrp->RemoveGrp(sel->text(0).toLatin1());
+
+            std::string groupName = sel->text(0).toStdString();
+            // must delete the tree item here because it and its children still
+            // hold a reference to the parameter group
             delete sel;
+
+            ParameterGroupItem* para = static_cast<ParameterGroupItem*>(parent);
+            para->_hcGrp->RemoveGrp(groupName.c_str());
         }
     }
 }
diff --git a/src/Mod/Cloud/App/AppCloud.cpp b/src/Mod/Cloud/App/AppCloud.cpp
index 3d18fa8e88..254b53c735 100644
--- a/src/Mod/Cloud/App/AppCloud.cpp
+++ b/src/Mod/Cloud/App/AppCloud.cpp
@@ -28,6 +28,8 @@
 
 #include <openssl/hmac.h>
 #include <openssl/pem.h>
+#include <openssl/md5.h>
+
 #include <curl/curl.h>
 
 #include <App/Application.h>
@@ -193,31 +195,15 @@ void Cloud::CloudWriter::checkText(DOMText* text) {
 
 void Cloud::CloudWriter::createBucket()
 {
-	printf("CREATING BUCKET %s\n", this->Bucket);
-        struct timeval tv;
-        struct tm *tm;
-        char date_formatted[256];
-        char StringToSign[1024];
-        unsigned char *digest;
-
+        struct Cloud::AmzData *RequestData;
         CURL *curl;
         CURLcode res;
 
         struct data_buffer curl_buffer;
 
-#if defined(FC_OS_WIN32)
-#else
-        gettimeofday(&tv,NULL);
-        tm = localtime(&tv.tv_sec);
-        strftime(date_formatted,256,"%a, %d %b %Y %T %z", tm);
-#endif
-
-        // CHANGEME
-        sprintf(StringToSign,"PUT\n\napplication/xml\n%s\n/%s/", date_formatted, this->Bucket);
-
-        // We have to use HMAC encoding and SHA1
-        digest=HMAC(EVP_sha1(),this->SecretKey,strlen(this->SecretKey),
-                (const unsigned char *)&StringToSign,strlen(StringToSign),NULL,NULL);
+	char path[1024];
+        sprintf(path, "/%s/", this->Bucket);
+        RequestData = Cloud::ComputeDigestAmzS3v2("PUT", "application/xml", path, this->SecretKey, NULL, 0);
 
         // Let's build the Header and call to curl
         curl_global_init(CURL_GLOBAL_ALL);
@@ -225,27 +211,22 @@ void Cloud::CloudWriter::createBucket()
         if ( curl )
         {
                 struct curl_slist *chunk = NULL;
-                char header_data[1024];
+		char Url[256];
                 // Let's build our own header
                 std::string strUrl(this->Url);
                 eraseSubStr(strUrl,"http://");
                 eraseSubStr(strUrl,"https://");
 
-                sprintf(header_data,"Host: %s", strUrl.c_str());
-                chunk = curl_slist_append(chunk, header_data);
-                sprintf(header_data,"Date: %s", date_formatted);
-                chunk = curl_slist_append(chunk, header_data);
-                chunk = curl_slist_append(chunk, "Content-Type: application/xml");
-                std::string digest_str;
-                digest_str=Base::base64_encode(digest,strlen((const char *)digest));
-                sprintf(header_data,"Authorization: AWS %s:%s", this->AccessKey,
-                digest_str.c_str());
-                chunk = curl_slist_append(chunk, header_data);
+                chunk = Cloud::BuildHeaderAmzS3v2( strUrl.c_str(), this->TcpPort, this->AccessKey, RequestData);
+
                 curl_easy_setopt(curl, CURLOPT_HTTPHEADER, chunk);
-//                curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
-                sprintf(header_data,"%s:%s/%s/", this->Url,this->TcpPort,
+
+                // Lets build the Url for our Curl call
+
+                sprintf(Url,"%s:%s/%s/", this->Url,this->TcpPort,
                                                     this->Bucket);
-                curl_easy_setopt(curl, CURLOPT_URL, header_data);
+                curl_easy_setopt(curl, CURLOPT_URL, Url);
+
                 curl_easy_setopt(curl, CURLOPT_UPLOAD, 1L);
                 curl_easy_setopt(curl, CURLOPT_PUT, 1L);
                 // curl read a file not a memory buffer (it shall be able to do it)
@@ -266,13 +247,113 @@ void Cloud::CloudWriter::createBucket()
         }
 }
 
-Cloud::CloudWriter::CloudWriter(const char* Url, const char* AccessKey, const char* SecretKey, const char* TcpPort, const char* Bucket)
+struct Cloud::AmzData *Cloud::ComputeDigestAmzS3v2(char *operation, char *data_type, const char *target, const char *Secret, const char *ptr, long size)
 {
+	struct AmzData *returnData;
         struct timeval tv;
         struct tm *tm;
         char date_formatted[256];
-        char StringToSign[1024];
-        unsigned char *digest;
+	char StringToSign[1024];
+	unsigned char *digest;
+	unsigned int HMACLength;
+        // Amazon S3 and Swift require the timezone to be define to GMT.
+        // As to simplify the conversion this is performed through the TZ
+        // environment variable and a call to localtime as to convert output of gettimeofday
+	returnData = ( struct Cloud::AmzData *) malloc(sizeof(struct Cloud::AmzData));
+
+	strcpy(returnData->ContentType, data_type);
+	
+#if defined(FC_OS_WIN32)
+        _putenv("TZ=GMT");
+#else
+        setenv("TZ","GMT",1);
+#endif
+        // We must check that the bucket exists or not. If not, we have to create it.
+        // We must request the bucketlist if we receive a 404 error. This means that it
+        // doesn't exist. The other option is that the content list is empty.
+        // This piece of code is the same as the Reader except we do not interpret it !
+#if defined(FC_OS_WIN32)
+#else
+        gettimeofday(&tv,NULL);
+        tm = localtime(&tv.tv_sec);
+        strftime(date_formatted,256,"%a, %d %b %Y %T %z", tm);
+#endif
+	returnData->MD5=NULL;
+	if ( strcmp(operation,"PUT") == 0 )
+	{
+		if (  ptr != NULL )
+		{
+	                returnData->MD5=Cloud::MD5Sum(ptr,size);
+			sprintf(StringToSign,"%s\n%s\n%s\n%s\n%s", operation, returnData->MD5, data_type, date_formatted, target);
+		}
+		else
+			sprintf(StringToSign,"%s\n\n%s\n%s\n%s", operation, data_type, date_formatted, target);
+	}
+	else
+		sprintf(StringToSign,"%s\n\n%s\n%s\n%s", operation, data_type, date_formatted, target);
+	// We have to use HMAC encoding and SHA1
+        digest=HMAC(EVP_sha1(),Secret,strlen(Secret),
+                (const unsigned char *)&StringToSign,strlen(StringToSign),NULL,&HMACLength);
+	returnData->digest = Base::base64_encode(digest,HMACLength);
+	strcpy(returnData->dateFormatted,date_formatted);
+	return returnData;
+	
+}
+
+char *Cloud::MD5Sum(const char *ptr, long size)
+{
+	char *output;
+	std::string local;
+	unsigned char result[MD5_DIGEST_LENGTH];
+	output=(char *)malloc(2*MD5_DIGEST_LENGTH*sizeof(char)+1);
+        MD5((unsigned char*) ptr, size, result);
+	local= Base::base64_encode(result,MD5_DIGEST_LENGTH);
+	strcpy(output,local.c_str());
+	return(output);
+}
+
+struct curl_slist *Cloud::BuildHeaderAmzS3v2(const char *Url, const char *TcpPort, const char *PublicKey, struct Cloud::AmzData *Data)
+{
+        char header_data[1024];
+	struct curl_slist *chunk = NULL;
+
+	// Build the Host: entry
+
+	sprintf(header_data,"Host: %s:%s", Url, TcpPort);
+        chunk = curl_slist_append(chunk, header_data);
+	
+	// Build the Date entry
+
+	sprintf(header_data,"Date: %s", Data->dateFormatted);
+	chunk = curl_slist_append(chunk, header_data);
+	
+	// Build the Content-Type entry
+
+	sprintf(header_data,"Content-Type:%s", Data->ContentType);
+	chunk = curl_slist_append(chunk, header_data);
+
+	// If ptr is not null we must compute the MD5-Sum as to validate later the ETag
+	// and add the MD5-Content: entry to the header
+	if ( Data->MD5 != NULL )
+	{
+		sprintf(header_data,"Content-MD5: %s", Data->MD5);
+		chunk = curl_slist_append(chunk, header_data);
+		// We don't need it anymore we can free it
+		free((void *)Data->MD5);
+	}
+
+	// build the Auth entry
+
+	sprintf(header_data,"Authorization: AWS %s:%s", PublicKey,
+                Data->digest.c_str());
+        chunk = curl_slist_append(chunk, header_data);
+
+	return chunk;
+}
+
+Cloud::CloudWriter::CloudWriter(const char* Url, const char* AccessKey, const char* SecretKey, const char* TcpPort, const char* Bucket)
+{
+        struct Cloud::AmzData *RequestData;
         CURL *curl;
         CURLcode res;
 
@@ -284,58 +365,31 @@ Cloud::CloudWriter::CloudWriter(const char* Url, const char* AccessKey, const ch
         this->TcpPort=TcpPort;
         this->Bucket=Bucket;
         this->FileName="";
-        // Amazon S3 and Swift require the timezone to be define to GMT.
-        // As to simplify the conversion this is performed through the TZ
-        // environment variable and a call to localtime as to convert output of gettimeofday
-#if defined(FC_OS_WIN32)
-        _putenv("TZ=GMT");
-#else
-        setenv("TZ","GMT",1);
-#endif
-	// We must check that the bucket exists or not. If not, we have to create it.
-	// We must request the bucketlist if we receive a 404 error. This means that it
-    // doesn't exist. The other option is that the content list is empty.
-	// This piece of code is the same as the Reader except we do not interpret it !
-#if defined(FC_OS_WIN32)
-#else
-        gettimeofday(&tv,NULL);
-        tm = localtime(&tv.tv_sec);
-        strftime(date_formatted,256,"%a, %d %b %Y %T %z", tm);
-#endif
-
-        sprintf(StringToSign,"GET\n\napplication/xml\n%s\n/%s/", date_formatted, this->Bucket);
-
-        // We have to use HMAC encoding and SHA1
-        digest=HMAC(EVP_sha1(),this->SecretKey,strlen(this->SecretKey),
-                (const unsigned char *)&StringToSign,strlen(StringToSign),NULL,NULL);
-
+	char path[1024];
+	sprintf(path,"/%s/", this->Bucket);
+	RequestData = Cloud::ComputeDigestAmzS3v2("GET", "application/xml", path, this->SecretKey, NULL, 0);
         // Let's build the Header and call to curl
         curl_global_init(CURL_GLOBAL_ALL);
         curl = curl_easy_init();
         if ( curl )
         {
-                struct curl_slist *chunk = NULL;
-                char header_data[1024];
                 // Let's build our own header
+		struct curl_slist *chunk = NULL;
+		char Url[256];
                 std::string strUrl(this->Url);
                 eraseSubStr(strUrl,"http://");
                 eraseSubStr(strUrl,"https://");
 
-                sprintf(header_data,"Host: %s:%s", strUrl.c_str(),
-                                                   this->TcpPort);
-                chunk = curl_slist_append(chunk, header_data);
-                sprintf(header_data,"Date: %s", date_formatted);
-                chunk = curl_slist_append(chunk, header_data);
-                chunk = curl_slist_append(chunk, "Content-Type: application/xml");
-                std::string digest_str;
-                digest_str=Base::base64_encode(digest,strlen((const char *)digest));
-                sprintf(header_data,"Authorization: AWS %s:%s", this->AccessKey,
-                digest_str.c_str());
-                chunk = curl_slist_append(chunk, header_data);
+		chunk = Cloud::BuildHeaderAmzS3v2( strUrl.c_str(), this->TcpPort, this->AccessKey, RequestData);
+
                 curl_easy_setopt(curl, CURLOPT_HTTPHEADER, chunk);
-                sprintf(header_data,"%s:%s/%s/", this->Url,this->TcpPort,
+
+		// Lets build the Url for our Curl call
+
+		sprintf(Url,"%s:%s/%s/", this->Url,this->TcpPort,
                                                     this->Bucket);
-                curl_easy_setopt(curl, CURLOPT_URL, header_data);
+                curl_easy_setopt(curl, CURLOPT_URL, Url);
+
                 curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, CurlWrite_CallbackFunc_StdString);
                 curl_easy_setopt(curl, CURLOPT_WRITEDATA, &s);
                 // curl read a file not a memory buffer (it shall be able to do it)
@@ -344,7 +398,8 @@ Cloud::CloudWriter::CloudWriter(const char* Url, const char* AccessKey, const ch
                       fprintf(stderr, "curl_easy_perform() failed: %s\n",
                         curl_easy_strerror(res));
                 curl_easy_cleanup(curl);
-
+		free( RequestData);
+		// Let's dump temporarly for debug purpose of s3v4 implementation
 
                 std::stringstream input(s);
 
@@ -458,11 +513,7 @@ Cloud::CloudReader::~CloudReader()
 
 Cloud::CloudReader::CloudReader(const char* Url, const char* AccessKey, const char* SecretKey, const char* TcpPort, const char* Bucket) 
 {
-        struct timeval tv;
-        struct tm *tm;
-        char date_formatted[256];
-        char StringToSign[1024];
-        unsigned char *digest;
+        struct Cloud::AmzData *RequestData;
         CURL *curl;
         CURLcode res;
 
@@ -475,58 +526,32 @@ Cloud::CloudReader::CloudReader(const char* Url, const char* AccessKey, const ch
         this->TcpPort=TcpPort;
         this->Bucket=Bucket;
 
-        // Amazon S3 and Swift require the timezone to be define to
-        // GMT. As to simplify the conversion this is performed through the TZ
-        // environment variable and a call to localtime as to convert output of gettimeofday
-#if defined(FC_OS_WIN32)
-        _putenv("TZ=GMT");
-#else
-        setenv("TZ","GMT",1);
-#endif
+	char path[1024];
+        sprintf(path,"/%s/", this->Bucket);
+        RequestData = Cloud::ComputeDigestAmzS3v2("GET", "application/xml", path, this->SecretKey, NULL, 0);
 
-        // We must get the directory content
-
-
-#if defined(FC_OS_WIN32)
-#else
-        gettimeofday(&tv,NULL);
-        tm = localtime(&tv.tv_sec);
-        strftime(date_formatted,256,"%a, %d %b %Y %T %z", tm);
-#endif
-
-        sprintf(StringToSign,"GET\n\napplication/xml\n%s\n/%s/", date_formatted, this->Bucket);
-
-        // We have to use HMAC encoding and SHA1
-        digest=HMAC(EVP_sha1(),this->SecretKey,strlen(this->SecretKey),
-                (const unsigned char *)&StringToSign,strlen(StringToSign),NULL,NULL);
 
         // Let's build the Header and call to curl
         curl_global_init(CURL_GLOBAL_ALL);
         curl = curl_easy_init();
         if ( curl )
         {
+		// Let's build our own header
                 struct curl_slist *chunk = NULL;
-                char header_data[1024];
-                // Let's build our own header
-		std::string strUrl(this->Url);
+                char Url[256];
+                std::string strUrl(this->Url);
                 eraseSubStr(strUrl,"http://");
                 eraseSubStr(strUrl,"https://");
 
-                sprintf(header_data,"Host: %s:%s", strUrl.c_str(),
-                                                   this->TcpPort);
-                chunk = curl_slist_append(chunk, header_data);
-                sprintf(header_data,"Date: %s", date_formatted);
-                chunk = curl_slist_append(chunk, header_data);
-                chunk = curl_slist_append(chunk, "Content-Type: application/xml");
-                std::string digest_str;
-                digest_str=Base::base64_encode(digest,strlen((const char *)digest));
-                sprintf(header_data,"Authorization: AWS %s:%s", this->AccessKey,
-                digest_str.c_str());
-                chunk = curl_slist_append(chunk, header_data);
+                chunk = Cloud::BuildHeaderAmzS3v2( strUrl.c_str(), this->TcpPort, this->AccessKey, RequestData);
+
                 curl_easy_setopt(curl, CURLOPT_HTTPHEADER, chunk);
-                sprintf(header_data,"%s:%s/%s/", this->Url,this->TcpPort,
+
+                sprintf(Url,"%s:%s/%s/", this->Url,this->TcpPort,
                                                     this->Bucket);
-                curl_easy_setopt(curl, CURLOPT_URL, header_data);
+                curl_easy_setopt(curl, CURLOPT_URL, Url);
+
+
                 curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, CurlWrite_CallbackFunc_StdString);
                 curl_easy_setopt(curl, CURLOPT_WRITEDATA, &s);
                 // curl read a file not a memory buffer (it shall be able to do it)
@@ -564,31 +589,16 @@ Cloud::CloudReader::CloudReader(const char* Url, const char* AccessKey, const ch
 
 void Cloud::CloudReader::DownloadFile(Cloud::CloudReader::FileEntry *entry)
 {
-        struct timeval tv;
-        struct tm *tm;
-        char date_formatted[256];
-        char StringToSign[1024];
-        unsigned char *digest;
+        struct Cloud::AmzData *RequestData;
         CURL *curl;
         CURLcode res;
 
         std::string s;
 
         // We must get the directory content
-
-
-#if defined(FC_OS_WIN32)
-#else
-        gettimeofday(&tv,NULL);
-        tm = localtime(&tv.tv_sec);
-        strftime(date_formatted,256,"%a, %d %b %Y %T %z", tm);
-#endif
-
-        // CHANGEME
-        sprintf(StringToSign,"GET\n\napplication/octet-stream\n%s\n/%s/%s", date_formatted, this->Bucket, entry->FileName);
-        // We have to use HMAC encoding and SHA1
-        digest=HMAC(EVP_sha1(),this->SecretKey,strlen(this->SecretKey),
-                (const unsigned char *)&StringToSign,strlen(StringToSign),NULL,NULL);
+	char path[1024];
+	sprintf(path, "/%s/%s", this->Bucket, entry->FileName);
+        RequestData = Cloud::ComputeDigestAmzS3v2("GET", "application/octet-stream", path, this->SecretKey, NULL, 0);
 
         // Let's build the Header and call to curl
         curl_global_init(CURL_GLOBAL_ALL);
@@ -596,26 +606,20 @@ void Cloud::CloudReader::DownloadFile(Cloud::CloudReader::FileEntry *entry)
         if ( curl )
         {
                 struct curl_slist *chunk = NULL;
-                char header_data[1024];
+                char Url[256];
                 // Let's build our own header
 		std::string strUrl(this->Url);
                 eraseSubStr(strUrl,"http://");
                 eraseSubStr(strUrl,"https://");
-                sprintf(header_data,"Host: %s:%s", strUrl.c_str(),
-                                                   this->TcpPort);
-                chunk = curl_slist_append(chunk, header_data);
-                sprintf(header_data,"Date: %s", date_formatted);
-                chunk = curl_slist_append(chunk, header_data);
-                chunk = curl_slist_append(chunk, "Content-Type: application/octet-stream");
-                std::string digest_str;
-                digest_str=Base::base64_encode(digest,strlen((const char *)digest));
-                sprintf(header_data,"Authorization: AWS %s:%s", this->AccessKey,
-                digest_str.c_str());
-                chunk = curl_slist_append(chunk, header_data);
+
+                chunk = Cloud::BuildHeaderAmzS3v2( strUrl.c_str(), this->TcpPort, this->AccessKey, RequestData);
+
                 curl_easy_setopt(curl, CURLOPT_HTTPHEADER, chunk);
-                sprintf(header_data,"%s:%s/%s/%s", this->Url,this->TcpPort,
-                                                    this->Bucket,entry->FileName);
-                curl_easy_setopt(curl, CURLOPT_URL, header_data);
+
+                sprintf(Url,"%s:%s/%s/%s", this->Url,this->TcpPort,
+                                                    this->Bucket, entry->FileName);
+                curl_easy_setopt(curl, CURLOPT_URL, Url);
+
 //                curl_easy_setopt(curl, CURLOPT_VERBOSE, 1);
                 curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, CurlWrite_CallbackFunc_StdString);
                 curl_easy_setopt(curl, CURLOPT_WRITEDATA, &s);
@@ -696,31 +700,14 @@ bool Cloud::CloudWriter::shouldWrite(const std::string& , const Base::Persistenc
 
 void Cloud::CloudWriter::pushCloud(const char *FileName, const char *data, long size)
 {
-        struct timeval tv;
-        struct tm *tm;
-        char date_formatted[256];
-        char StringToSign[1024];
-        unsigned char *digest;
-        // char my_data[1024]="a que coucou";
-
+        struct Cloud::AmzData *RequestData;
         CURL *curl;
         CURLcode res;
+	struct data_buffer curl_buffer;
 
-        struct data_buffer curl_buffer;
-
-#if defined(FC_OS_WIN32)
-#else
-        gettimeofday(&tv,NULL);
-        tm = localtime(&tv.tv_sec);
-        strftime(date_formatted,256,"%a, %d %b %Y %T %z", tm);
-#endif
-
-        // CHANGEME
-        sprintf(StringToSign,"PUT\n\napplication/octet-stream\n%s\n/%s/%s", date_formatted, this->Bucket, FileName);
-
-        // We have to use HMAC encoding and SHA1
-        digest=HMAC(EVP_sha1(),this->SecretKey,strlen(this->SecretKey),
-                (const unsigned char *)&StringToSign,strlen(StringToSign),NULL,NULL);
+	char path[1024];
+        sprintf(path, "/%s/%s", this->Bucket, FileName);
+        RequestData = Cloud::ComputeDigestAmzS3v2("PUT", "application/octet-stream", path, this->SecretKey, data, size);
 
         // Let's build the Header and call to curl
         curl_global_init(CURL_GLOBAL_ALL);
@@ -728,28 +715,26 @@ void Cloud::CloudWriter::pushCloud(const char *FileName, const char *data, long
         if ( curl )
         {
                 struct curl_slist *chunk = NULL;
-                char header_data[1024];
+		char Url[256];
                 // Let's build our own header
 		std::string strUrl(this->Url);
 		eraseSubStr(strUrl,"http://");
 		eraseSubStr(strUrl,"https://");
-				
-                sprintf(header_data,"Host: %s:%s", strUrl.c_str(),
-                                                   this->TcpPort);
-                chunk = curl_slist_append(chunk, header_data);
-                sprintf(header_data,"Date: %s", date_formatted);
-                chunk = curl_slist_append(chunk, header_data);
-                chunk = curl_slist_append(chunk, "Content-Type: application/octet-stream");
-                std::string digest_str;
-                digest_str=Base::base64_encode(digest,strlen((const char *)digest));
-                sprintf(header_data,"Authorization: AWS %s:%s", this->AccessKey,
-                digest_str.c_str());
-                chunk = curl_slist_append(chunk, header_data);
+
+
+		chunk = Cloud::BuildHeaderAmzS3v2( strUrl.c_str(), this->TcpPort, this->AccessKey, RequestData);
+
                 curl_easy_setopt(curl, CURLOPT_HTTPHEADER, chunk);
-//                curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
-                sprintf(header_data,"%s:%s/%s/%s", this->Url,this->TcpPort,
+
+                // Lets build the Url for our Curl call
+
+                sprintf(Url,"%s:%s/%s/%s", this->Url,this->TcpPort,
                                                     this->Bucket,FileName);
-                curl_easy_setopt(curl, CURLOPT_URL, header_data);
+                curl_easy_setopt(curl, CURLOPT_URL, Url);
+
+				
+//                curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
+
                 curl_easy_setopt(curl, CURLOPT_UPLOAD, 1L);
                 curl_easy_setopt(curl, CURLOPT_PUT, 1L);
                 // curl read a file not a memory buffer (it shall be able to do it)
diff --git a/src/Mod/Cloud/App/AppCloud.h b/src/Mod/Cloud/App/AppCloud.h
index 1650d73425..b95dc6c136 100644
--- a/src/Mod/Cloud/App/AppCloud.h
+++ b/src/Mod/Cloud/App/AppCloud.h
@@ -47,8 +47,19 @@ XERCES_CPP_NAMESPACE_END
 
 namespace Cloud {
 
+struct AmzData {
+	std::string digest;
+	char dateFormatted[256];
+	char ContentType[256];
+	char Host[256];
+	char *MD5;
+};
+
 void eraseSubStr(std::string & Str, const std::string & toErase);
 size_t CurlWrite_CallbackFunc_StdString(void *contents, size_t size, size_t nmemb, std::string *s);
+struct AmzData *ComputeDigestAmzS3v2(char *operation, char *data_type, const char *target, const char *Secret, const char *ptr, long size);
+struct curl_slist *BuildHeaderAmzS3v2(const char *Url, const char *TcpPort, const char *PublicKey, struct AmzData *Data);
+char *MD5Sum(const char *ptr, long size);
 
 class CloudAppExport CloudReader
 {
diff --git a/src/Mod/Import/App/dxf.cpp b/src/Mod/Import/App/dxf.cpp
index c8ac9c12a3..abc8b09526 100644
--- a/src/Mod/Import/App/dxf.cpp
+++ b/src/Mod/Import/App/dxf.cpp
@@ -31,10 +31,16 @@ Base::Vector3d toVector3d(const double* a)
 
 CDxfWrite::CDxfWrite(const char* filepath) :
 //TODO: these should probably be parms in config file
-m_entityHandle(0x300),
-m_layerHandle(0x30),
-m_blockHandle(0x210),
-m_blkRecordHandle(0x110),
+//handles:
+//boilerplate 0 - A00
+//used by dxf.cpp A01 - FFFE
+//ACAD HANDSEED  FFFF
+
+m_handle(0xA00),                       //room for 2560 handles in boilerplate files
+//m_entityHandle(0x300),               //don't need special ranges for handles
+//m_layerHandle(0x30),
+//m_blockHandle(0x210),
+//m_blkRecordHandle(0x110),
 m_polyOverride(false),
 m_layerName("none")
 {
@@ -435,40 +441,53 @@ std::string CDxfWrite::getPlateFile(std::string fileSpec)
     return outString.str();
 }
 
-std::string CDxfWrite::getEntityHandle(void)
+std::string CDxfWrite::getHandle(void)
 {
-    m_entityHandle++;
+    m_handle++;
     std::stringstream ss;
     ss << std::uppercase << std::hex << std::setfill('0') << std::setw(2);
-    ss << m_entityHandle;
+    ss << m_handle;
     return ss.str();
 }
 
+std::string CDxfWrite::getEntityHandle(void)
+{
+    return getHandle();
+//    m_entityHandle++;
+//    std::stringstream ss;
+//    ss << std::uppercase << std::hex << std::setfill('0') << std::setw(2);
+//    ss << m_entityHandle;
+//    return ss.str();
+}
+
 std::string CDxfWrite::getLayerHandle(void)
 {
-    m_layerHandle++;
-    std::stringstream ss;
-    ss << std::uppercase << std::hex << std::setfill('0') << std::setw(2);
-    ss << m_layerHandle;
-    return ss.str();
+    return getHandle();
+//    m_layerHandle++;
+//    std::stringstream ss;
+//    ss << std::uppercase << std::hex << std::setfill('0') << std::setw(2);
+//    ss << m_layerHandle;
+//    return ss.str();
 }
 
 std::string CDxfWrite::getBlockHandle(void)
 {
-    m_blockHandle++;
-    std::stringstream ss;
-    ss << std::uppercase << std::hex << std::setfill('0') << std::setw(2);
-    ss << m_blockHandle;
-    return ss.str();
+    return getHandle();
+//    m_blockHandle++;
+//    std::stringstream ss;
+//    ss << std::uppercase << std::hex << std::setfill('0') << std::setw(2);
+//    ss << m_blockHandle;
+//    return ss.str();
 }
 
 std::string CDxfWrite::getBlkRecordHandle(void)
 {
-    m_blkRecordHandle++;
-    std::stringstream ss;
-    ss << std::uppercase << std::hex << std::setfill('0') << std::setw(2);
-    ss << m_blkRecordHandle;
-    return ss.str();
+    return getHandle();
+//    m_blkRecordHandle++;
+//    std::stringstream ss;
+//    ss << std::uppercase << std::hex << std::setfill('0') << std::setw(2);
+//    ss << m_blkRecordHandle;
+//    return ss.str();
 }
 
 void CDxfWrite::addBlockName(std::string b, std::string h) 
diff --git a/src/Mod/Import/App/dxf.h b/src/Mod/Import/App/dxf.h
index 505c99a7ab..5de6bb7700 100644
--- a/src/Mod/Import/App/dxf.h
+++ b/src/Mod/Import/App/dxf.h
@@ -145,6 +145,7 @@ protected:
     //! copy boiler plate file
     std::string getPlateFile(std::string fileSpec);
     void setDataDir(std::string s) { m_dataDir = s; }
+    std::string getHandle(void);
     std::string getEntityHandle(void);
     std::string getLayerHandle(void);
     std::string getBlockHandle(void);
@@ -152,6 +153,7 @@ protected:
 
     std::string m_optionSource;
     int m_version;
+    int m_handle;
     int m_entityHandle;
     int m_layerHandle;
     int m_blockHandle;
diff --git a/src/Mod/Import/DxfPlate/header14.rub b/src/Mod/Import/DxfPlate/header14.rub
index 5253db1285..a6cf3fa447 100644
--- a/src/Mod/Import/DxfPlate/header14.rub
+++ b/src/Mod/Import/DxfPlate/header14.rub
@@ -31,8 +31,24 @@ $CMLSTYLE
   2
 STANDARD
   9
+$PEXTMAX
+ 10
+50
+ 20
+50
+ 30
+50
+  9
+$PEXTMIN
+ 10
+0
+ 20
+0
+ 30
+0
+  9
 $HANDSEED
   5
-FFF
+FFFF
   0
 ENDSEC
diff --git a/src/Mod/Import/DxfPlate/objects14.rub b/src/Mod/Import/DxfPlate/objects14.rub
index 8313b799b7..e8e2adb95b 100644
--- a/src/Mod/Import/DxfPlate/objects14.rub
+++ b/src/Mod/Import/DxfPlate/objects14.rub
@@ -5,7 +5,7 @@ OBJECTS
   0
 DICTIONARY
   5
-500
+F000
 330
 0
 100
@@ -13,13 +13,13 @@ AcDbDictionary
   3
 ACAD_GROUP
 350
-501
+F001
   0
 DICTIONARY
   5
-501
+F001
 330
-500
+F000
 100
 AcDbDictionary
   0
diff --git a/src/Mod/Import/DxfPlate/tables214.rub b/src/Mod/Import/DxfPlate/tables214.rub
index a3b91cb934..040b26821e 100644
--- a/src/Mod/Import/DxfPlate/tables214.rub
+++ b/src/Mod/Import/DxfPlate/tables214.rub
@@ -3,7 +3,7 @@ TABLE
   2
 STYLE
   5
-60
+70
 330
 0
 100
@@ -13,9 +13,9 @@ AcDbSymbolTable
   0
 STYLE
   5
-61
+71
 330
-60
+70
 100
 AcDbSymbolTableRecord
 100
@@ -41,9 +41,9 @@ arial.ttf
   0
 STYLE
   5
-62
+72
 330
-60
+70
 100
 AcDbSymbolTableRecord
 100
@@ -73,7 +73,7 @@ TABLE
   2
 VIEW
   5
-63
+73
 330
 0
 100
@@ -87,7 +87,7 @@ TABLE
   2
 UCS
   5
-64
+74
 330
 0
 100
@@ -101,7 +101,7 @@ TABLE
   2
 APPID
   5
-65
+75
 330
 0
 100
@@ -111,9 +111,9 @@ AcDbSymbolTable
   0
 APPID
   5
-66
+76
 330
-65
+75
 100
 AcDbSymbolTableRecord
 100
@@ -125,9 +125,9 @@ ACAD
   0
 APPID
   5
-67
+77
 330
-65
+75
 100
 AcDbSymbolTableRecord
 100
@@ -143,7 +143,7 @@ TABLE
   2
 DIMSTYLE
   5
-68
+78
 330
 0
 100
@@ -153,9 +153,9 @@ AcDbSymbolTable
   0
 DIMSTYLE
 105
-69
+79
 330
-68
+78
 100
 AcDbSymbolTableRecord
 100
@@ -253,7 +253,7 @@ STANDARD
 274
      3
 340
-61
+71
 275
      0
 280
diff --git a/src/Mod/OpenSCAD/InitGui.py b/src/Mod/OpenSCAD/InitGui.py
index 16335a0d0e..0a5d4db5f4 100644
--- a/src/Mod/OpenSCAD/InitGui.py
+++ b/src/Mod/OpenSCAD/InitGui.py
@@ -38,9 +38,11 @@ class OpenSCADWorkbench ( Workbench ):
     def __init__(self):
         self.__class__.Icon = FreeCAD.getResourceDir() + "Mod/OpenSCAD/Resources/icons/OpenSCADWorkbench.svg"
         self.__class__.MenuText = "OpenSCAD"
-        self.__class__.ToolTip = "OpenSCAD is an application for creating solid 3D CAD." + '\n' +
-                                 "FreeCAD utizes OpenSCAD's capability as a script-only based modeller that uses its own description language" + '\n' +
-                                 "Note: the Mesh workbench heavily uses the boolean operations of this workbench because they are quite robust"
+        self.__class__.ToolTip = (
+            "OpenSCAD is an application for creating solid 3D CAD.\n"
+            "FreeCAD utizes OpenSCAD's capability as a script-only based modeller that uses its own description language\n"
+            "Note: the Mesh workbench heavily uses the boolean operations of this workbench because they are quite robust"
+        )
 
     def Initialize(self):
         def QT_TRANSLATE_NOOP(scope, text):
diff --git a/src/Mod/TechDraw/Gui/QGIViewDimension.cpp b/src/Mod/TechDraw/Gui/QGIViewDimension.cpp
index 2c0df20fe9..969250b500 100644
--- a/src/Mod/TechDraw/Gui/QGIViewDimension.cpp
+++ b/src/Mod/TechDraw/Gui/QGIViewDimension.cpp
@@ -538,21 +538,26 @@ void QGIViewDimension::updateDim()
     if ( vp == nullptr ) {
         return;
     }
- 
+
 //    QString labelText = QString::fromUtf8(dim->getFormatedValue().c_str());
     //want this split into value and unit
     QString labelText = QString::fromUtf8(dim->getFormatedValue(1).c_str()); //just the number
     QString unitText  = QString::fromUtf8(dim->getFormatedValue(2).c_str()); //just the unit
-    
+    QString arbText = QString::fromUtf8(dim->FormatSpec.getValue());
+
     QFont font = datumLabel->getFont();
     font.setFamily(QString::fromUtf8(vp->Font.getValue()));
     font.setPixelSize(calculateFontPixelSize(vp->Fontsize.getValue()));
     datumLabel->setFont(font);
 
     prepareGeometryChange();
-    datumLabel->setDimString(labelText);
-    datumLabel->setTolString();
-    datumLabel->setUnitString(unitText);
+    if (dim->Arbitrary.getValue()) {
+        datumLabel->setDimString(arbText);
+    } else {
+        datumLabel->setDimString(labelText);
+        datumLabel->setTolString();
+        datumLabel->setUnitString(unitText);
+    }
     datumLabel->setPosFromCenter(datumLabel->X(),datumLabel->Y());
 
     datumLabel->setFramed(dim->TheoreticalExact.getValue());
diff --git a/src/Mod/Test/BaseTests.py b/src/Mod/Test/BaseTests.py
index ba12d8a43b..ffc7cb364b 100644
--- a/src/Mod/Test/BaseTests.py
+++ b/src/Mod/Test/BaseTests.py
@@ -113,8 +113,8 @@ class ParameterTestCase(unittest.TestCase):
         self.failUnless(self.TestPar.HasGroup("44"),"Test on created group failed")
         # check on Deletion
         self.TestPar.RemGroup("44")
-        self.failUnless(not self.TestPar.HasGroup("44"),"Test on delete group failed")
-        Temp =0
+        self.failUnless(self.TestPar.HasGroup("44"),"A referenced group must not be deleted")
+        Temp = 0
 
         #check on special conditions
     def testInt(self):
diff --git a/src/WindowsInstaller/README.md b/src/WindowsInstaller/README.md
index f1bc9aa0ec..dda44646f6 100644
--- a/src/WindowsInstaller/README.md
+++ b/src/WindowsInstaller/README.md
@@ -20,14 +20,14 @@ To build the installer you can do the following:
    (You can alternatively get nsProcess from https://nsis.sourceforge.io/NsProcess_plugin)
 7. Copy all FreeCAD files to the folder "~\FreeCAD"
    e.g. "C:\FreeCAD\Installer\FreeCAD"
-8. If you use compiled FreeCAD using another MSVC version than MSVC 2015, copy
+8. If you use compiled FreeCAD using another MSVC version than MSVC 2017, copy
    its distributable DLLs to the folder FILES_DEPS (see step 2).
 9. Right-click on the file FreeCAD-installer.nsi and choose "Compile NSIS script"
    to compile the installer
-10. The folder ~\MSVCRedist contains already all MSVC 2015 redistributable DLLs necessary
-   for FreeCAD. If another MSVC version was used to compile FreeCAD, replace the DLLs by
+10. The folder ~\MSVCRedist contains already all MSVC 2017 x64 redistributable DLLs necessary
+   for FreeCAD 0.19dev. If another MSVC version was used to compile FreeCAD, replace the DLLs by
    the ones of the used MSVC. (They are usually available in the folder
-   C:\Program Files (x86)\MSVC2xxx\VC\redist)
+   C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Redist\MSVC)
 
 For test builds of the installer you can turn off the compression. This speeds up
 the build time for the installer a lot but increases its file size. The compression
diff --git a/src/WindowsInstaller/Settings.nsh b/src/WindowsInstaller/Settings.nsh
index c12ce26854..b4d66973cb 100644
--- a/src/WindowsInstaller/Settings.nsh
+++ b/src/WindowsInstaller/Settings.nsh
@@ -16,11 +16,12 @@ SetCompressor /SOLID lzma
 # Version number
 
 !define APP_VERSION_MAJOR 0
-!define APP_VERSION_MINOR 18
+!define APP_VERSION_MINOR 19
 !define APP_VERSION_REVISION 0
-!define APP_VERSION_EMERGENCY "" # use "1" for an emergency release of FreeCAD otherwise ""
+!define APP_VERSION_EMERGENCY "rev18542" # use "1" for an emergency release of FreeCAD otherwise ""
+	# alternatively you can use APP_VERSION_EMERGENCY for a custom suffix of the version number
 !define APP_EMERGENCY_DOT "" # use "." for an emergency release of FreeCAD otherwise ""
-!define APP_VERSION_BUILD 10 # Start with 1 for the installer releases of each version
+!define APP_VERSION_BUILD 1 # Start with 1 for the installer releases of each version
 
 !define APP_VERSION "${APP_VERSION_MAJOR}.${APP_VERSION_MINOR}.${APP_VERSION_REVISION}${APP_EMERGENCY_DOT}${APP_VERSION_EMERGENCY}" # Version to display
 
diff --git a/src/WindowsInstaller/include/declarations.nsh b/src/WindowsInstaller/include/declarations.nsh
index 056e89a1cd..5b79a4bfb3 100644
--- a/src/WindowsInstaller/include/declarations.nsh
+++ b/src/WindowsInstaller/include/declarations.nsh
@@ -1,4 +1,4 @@
-/*
+/*
 declaration.nsh
 
 Configuration and variables of FreeCAD installer
@@ -32,8 +32,8 @@ Configuration and variables of FreeCAD installer
 !define APP_WIKI_INFO "${APP_NAME} Wiki"
 !define APP_COPYRIGHT "${APP_NAME} is Copyright © 2001-${COPYRIGHT_YEAR} by the ${APP_NAME} Team"
 
-!define APP_RUN "bin\FreeCAD.exe"
-!define BIN_FREECAD "FreeCAD.exe"
+!define APP_RUN "bin\${APP_NAME}.exe"
+!define BIN_FREECAD "${APP_NAME}.exe"
 
 !define APP_REGKEY "Software\${APP_NAME}${APP_SERIES_KEY}" # like "FreeCAD0180"
 !define APP_REGKEY_SETUP "${APP_REGKEY}\Setup"
diff --git a/src/WindowsInstaller/include/init.nsh b/src/WindowsInstaller/include/init.nsh
index 7d05feabfa..145a38d025 100644
--- a/src/WindowsInstaller/include/init.nsh
+++ b/src/WindowsInstaller/include/init.nsh
@@ -130,7 +130,10 @@ Function .onInit
    ${endif} 
   ${next}
   
-  ${if} $OldVersionNumber > ${APP_SERIES_KEY}
+  # NSIS cannot handle numbers with leading zero, thus cut it off before comparing
+  StrCpy $1 $OldVersionNumber "" 1
+  StrCpy $2 ${APP_SERIES_KEY} "" 1
+  ${if} $1 > $2
    # store the version number and reformat it temporarily for the error message
    StrCpy $R0 $OldVersionNumber
    StrCpy $OldVersionNumber $R5
diff --git a/src/WindowsInstaller/setup/configure.nsh b/src/WindowsInstaller/setup/configure.nsh
index d91c8ca3b4..7b576fae4e 100644
--- a/src/WindowsInstaller/setup/configure.nsh
+++ b/src/WindowsInstaller/setup/configure.nsh
@@ -43,7 +43,7 @@ Section -InstallData
   
   WriteRegStr SHCTX ${APP_UNINST_KEY} "UninstallString" '"$INSTDIR\${SETUP_UNINSTALLER}"'
   WriteRegStr SHCTX ${APP_UNINST_KEY} "DisplayVersion" "${APP_VERSION}"
-  WriteRegStr SHCTX ${APP_UNINST_KEY} "DisplayIcon" "$INSTDIR\bin\FreeCAD.exe"
+  WriteRegStr SHCTX ${APP_UNINST_KEY} "DisplayIcon" "$INSTDIR\bin\${APP_NAME}.exe"
   WriteRegStr SHCTX ${APP_UNINST_KEY} "URLUpdateInfo" "${APP_WEBPAGE}"
   WriteRegStr SHCTX ${APP_UNINST_KEY} "URLInfoAbout" "https://www.freecadweb.org/"
   WriteRegStr SHCTX ${APP_UNINST_KEY} "Publisher" "${APP_NAME} Team"
@@ -53,10 +53,15 @@ Section -InstallData
   WriteRegStr SHCTX ${APP_UNINST_KEY} "StartMenu" "$SMPROGRAMS\$StartmenuFolder"
   
   # if we install over an older existing version, remove the old uninstaller information
-  ${if} $OldVersionNumber < ${APP_SERIES_KEY}
+  # NSIS cannot handle numbers with leading zero, thus cut it off before comparing
+  StrCpy $1 $OldVersionNumber "" 1
+  StrCpy $2 ${APP_SERIES_KEY} "" 1
+  ${if} $1 < $2
    DeleteRegKey SHCTX "Software\Microsoft\Windows\CurrentVersion\Uninstall\${APP_NAME}$OldVersionNumber"
+   DeleteRegKey SHCTX "SOFTWARE\${APP_NAME}$OldVersionNumber"
    # also delete in the case of an emergency release
    DeleteRegKey SHCTX "Software\Microsoft\Windows\CurrentVersion\Uninstall\${APP_NAME}$OldVersionNumber1"
+   DeleteRegKey SHCTX "SOFTWARE\${APP_NAME}$OldVersionNumber1"
   ${endif}
   
 SectionEnd
diff --git a/src/WindowsInstaller/setup/install.nsh b/src/WindowsInstaller/setup/install.nsh
index 3ba5ababce..cc186b4a25 100644
--- a/src/WindowsInstaller/setup/install.nsh
+++ b/src/WindowsInstaller/setup/install.nsh
@@ -15,7 +15,7 @@ Section -ProgramFiles SecProgramFiles
   # be installed directly to C:\programs - the uninstaller will then delete the whole
   # C:\programs directory
   StrCpy $String $INSTDIR
-  StrCpy $Search "FreeCAD"
+  StrCpy $Search ${APP_NAME}
   Call StrPoint # function from Utils.nsh
   ${if} $Pointer == "-1"
    StrCpy $INSTDIR "$INSTDIR\${APP_DIR}"
@@ -43,6 +43,7 @@ Section -ProgramFiles SecProgramFiles
   File /r "${FILES_FREECAD}\Ext"
   File /r "${FILES_FREECAD}\lib"
   File /r "${FILES_FREECAD}\Mod"
+  File /r "${FILES_FREECAD}\resources"
     
   # Create uninstaller
   WriteUninstaller "$INSTDIR\${SETUP_UNINSTALLER}"