diff --git a/src/Mod/Part/App/PartFeature.cpp b/src/Mod/Part/App/PartFeature.cpp
index ab22149a38..d42be05ca7 100644
--- a/src/Mod/Part/App/PartFeature.cpp
+++ b/src/Mod/Part/App/PartFeature.cpp
@@ -1450,9 +1450,13 @@ void Feature::onChanged(const App::Property* prop)
             if (!this->Shape.getValue().IsNull()) {
                 try {
                     p.fromMatrix(this->Shape.getShape().getTransform());
+#ifdef FC_USE_TNP_FIX
+                    this->Placement.setValueIfChanged(p);
+#else
                     if (p != this->Placement.getValue()) {
                         this->Placement.setValue(p);
                     }
+#endif
                 }
                 catch (const Base::ValueError&) {
                 }
diff --git a/src/Mod/Part/App/PropertyTopoShape.cpp b/src/Mod/Part/App/PropertyTopoShape.cpp
index 75d8e48f73..1283a6007c 100644
--- a/src/Mod/Part/App/PropertyTopoShape.cpp
+++ b/src/Mod/Part/App/PropertyTopoShape.cpp
@@ -79,6 +79,9 @@ void PropertyPartShape::setValue(const TopoShape& sh)
             _Shape.Hasher = obj->getDocument()->getStringHasher();
             _Shape.hashChildMaps();
         }
+        if ( ! _Shape.isNull() && ! _Shape.isValid() ) {
+            _Shape.fix();
+        }
     }
     hasSetValue();
     _Ver.clear();
diff --git a/src/Mod/Part/App/TopoShape.cpp b/src/Mod/Part/App/TopoShape.cpp
index cf6acf1ba1..9db1b05622 100644
--- a/src/Mod/Part/App/TopoShape.cpp
+++ b/src/Mod/Part/App/TopoShape.cpp
@@ -645,6 +645,7 @@ Base::Matrix4D TopoShape::getTransform() const
 {
     Base::Matrix4D mtrx;
     gp_Trsf Trf = _Shape.Location().Transformation();
+    Trf.SetScaleFactor(1.0);
     convertToMatrix(Trf, mtrx);
     return mtrx;
 }
@@ -3034,9 +3035,10 @@ TopoDS_Shape TopoShape::transformGShape(const Base::Matrix4D& rclTrf, bool copy)
     mat.SetValue(1,4,rclTrf[0][3]);
     mat.SetValue(2,4,rclTrf[1][3]);
     mat.SetValue(3,4,rclTrf[2][3]);
-
+    // this copy step seems to eliminate Part.OCCError: gp_GTrsf::Trsf() - non-orthogonal GTrsf
+    BRepBuilderAPI_Copy copier(this->_Shape);
     // geometric transformation
-    BRepBuilderAPI_GTransform mkTrf(this->_Shape, mat, copy);
+    BRepBuilderAPI_GTransform mkTrf(copier.Shape(), mat, copy);
     return mkTrf.Shape();
 }
 
diff --git a/src/Mod/PartDesign/PartDesignTests/TestTopologicalNamingProblem.py b/src/Mod/PartDesign/PartDesignTests/TestTopologicalNamingProblem.py
index ceaa68163e..5d3db9f3ef 100644
--- a/src/Mod/PartDesign/PartDesignTests/TestTopologicalNamingProblem.py
+++ b/src/Mod/PartDesign/PartDesignTests/TestTopologicalNamingProblem.py
@@ -580,7 +580,7 @@ class TestTopologicalNamingProblem(unittest.TestCase):
         self.Doc.recompute()
         # Assert
         self.assertEqual(len(body.Shape.childShapes()), 1)
-        self.assertEqual(body.Shape.childShapes()[0].ElementMapSize, 26)
+        self.assertEqual(body.Shape.childShapes()[0].ElementMapSize, 30)
 
     def testPartDesignElementMapPocket(self):
         pass  # TODO
diff --git a/tests/src/Mod/Part/App/TopoShapeExpansion.cpp b/tests/src/Mod/Part/App/TopoShapeExpansion.cpp
index 20c9d652f9..3230a490f2 100644
--- a/tests/src/Mod/Part/App/TopoShapeExpansion.cpp
+++ b/tests/src/Mod/Part/App/TopoShapeExpansion.cpp
@@ -1815,7 +1815,7 @@ TEST_F(TopoShapeExpansionTest, makeElementThickSolid)
 
     // Note:  Cannot do an elementsMatch here because the oldest OCCT treats ThickSolid a little
     // differently.  So, just mae sure the size is right, and something has a THK in it.
-    for (auto element : elements) {
+    for (auto& element : elements) {
         if (element.second.find("THK") > 0) {
             EXPECT_TRUE(1);
             break;