diff --git a/code/X3DImporter_Postprocess.cpp b/code/X3DImporter_Postprocess.cpp
index 0e3f3a8ae..390ef8995 100644
--- a/code/X3DImporter_Postprocess.cpp
+++ b/code/X3DImporter_Postprocess.cpp
@@ -48,6 +48,7 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include "X3DImporter.hpp"
 
 // Header files, Assimp.
+#include <assimp/ai_assert.h>
 #include "StandardShapes.h"
 #include "StringUtils.h"
 
@@ -357,6 +358,7 @@ void X3DImporter::Postprocess_BuildMesh(const CX3DImporter_NodeElement& pNodeEle
 		// copy additional information from children
 		for(std::list<CX3DImporter_NodeElement*>::iterator ch_it = tnemesh.Child.begin(); ch_it != tnemesh.Child.end(); ch_it++)
 		{
+			ai_assert(*pMesh);
 			if((*ch_it)->Type == CX3DImporter_NodeElement::ENET_Color)
 				MeshGeometry_AddColor(**pMesh, tnemesh.CoordIndex, tnemesh.ColorIndex, ((CX3DImporter_NodeElement_Color*)*ch_it)->Value, tnemesh.ColorPerVertex);
 			else if((*ch_it)->Type == CX3DImporter_NodeElement::ENET_ColorRGBA)
@@ -389,6 +391,7 @@ void X3DImporter::Postprocess_BuildMesh(const CX3DImporter_NodeElement& pNodeEle
 		// copy additional information from children
 		for(std::list<CX3DImporter_NodeElement*>::iterator ch_it = tnemesh.Child.begin(); ch_it != tnemesh.Child.end(); ch_it++)
 		{
+			ai_assert(*pMesh);
 			if((*ch_it)->Type == CX3DImporter_NodeElement::ENET_Color)
 				MeshGeometry_AddColor(**pMesh, tnemesh.CoordIndex, tnemesh.ColorIndex, ((CX3DImporter_NodeElement_Color*)*ch_it)->Value, tnemesh.ColorPerVertex);
 			else if((*ch_it)->Type == CX3DImporter_NodeElement::ENET_ColorRGBA)
@@ -446,6 +449,7 @@ void X3DImporter::Postprocess_BuildMesh(const CX3DImporter_NodeElement& pNodeEle
 		// copy additional information from children
 		for(std::list<CX3DImporter_NodeElement*>::iterator ch_it = tnemesh.Child.begin(); ch_it != tnemesh.Child.end(); ch_it++)
 		{
+			ai_assert(*pMesh);
 			if((*ch_it)->Type == CX3DImporter_NodeElement::ENET_Color)
 				MeshGeometry_AddColor(**pMesh, ((CX3DImporter_NodeElement_Color*)*ch_it)->Value, true);
 			else if((*ch_it)->Type == CX3DImporter_NodeElement::ENET_ColorRGBA)
@@ -475,6 +479,7 @@ void X3DImporter::Postprocess_BuildMesh(const CX3DImporter_NodeElement& pNodeEle
 		// copy additional information from children
 		for(std::list<CX3DImporter_NodeElement*>::iterator ch_it = tnemesh.Child.begin(); ch_it != tnemesh.Child.end(); ch_it++)
 		{
+			ai_assert(*pMesh);
 			if((*ch_it)->Type == CX3DImporter_NodeElement::ENET_Color)
 				MeshGeometry_AddColor(**pMesh, ((CX3DImporter_NodeElement_Color*)*ch_it)->Value, true);
 			else if((*ch_it)->Type == CX3DImporter_NodeElement::ENET_ColorRGBA)
@@ -550,6 +555,7 @@ void X3DImporter::Postprocess_BuildMesh(const CX3DImporter_NodeElement& pNodeEle
 		// copy additional information from children
 		for(std::list<CX3DImporter_NodeElement*>::iterator ch_it = tnemesh.Child.begin(); ch_it != tnemesh.Child.end(); ch_it++)
 		{
+			ai_assert(*pMesh);
 			if((*ch_it)->Type == CX3DImporter_NodeElement::ENET_Color)
 				MeshGeometry_AddColor(**pMesh, ((CX3DImporter_NodeElement_Color*)*ch_it)->Value, tnemesh.ColorPerVertex);
 			else if((*ch_it)->Type == CX3DImporter_NodeElement::ENET_ColorRGBA)
@@ -584,6 +590,7 @@ void X3DImporter::Postprocess_BuildMesh(const CX3DImporter_NodeElement& pNodeEle
 		// copy additional information from children
 		for(std::list<CX3DImporter_NodeElement*>::iterator ch_it = tnemesh.Child.begin(); ch_it != tnemesh.Child.end(); ch_it++)
 		{
+			ai_assert(*pMesh);
 			if((*ch_it)->Type == CX3DImporter_NodeElement::ENET_Color)
 				MeshGeometry_AddColor(**pMesh, ((CX3DImporter_NodeElement_Color*)*ch_it)->Value, tnemesh.ColorPerVertex);
 			else if((*ch_it)->Type == CX3DImporter_NodeElement::ENET_ColorRGBA)