One common issue when trying to compile objects using XtoMDL in ModelConverterX is that XtoMDL can throw very unclear error messages when the XtoMDL tool is missing one of its prerequisites. For example the FSX XtoMDL needs a very specific DirectX version to the installed and different P3D XtoMDL versions depend on different C++ redistributable package versions. For a user it is often not clear that the error throws is related to such a prerequisites.
In the last development release of ModelConverterX I have made a change. The tool will now check if the right prerequisites are installed before you use XtoMDL and it will give a clear error message (including a download link) in case something is missing. That should make it a lot easier to make sure XtoMDL is working fine.
There is one big catch, on my machine I had all the prerequisites installed already of course. So I was not able to test it well in a situation where things are missing. So if you encounter any weird situations where ModelConverterX reports invalid prerequisites where it shouldn’t or where after installing the prerequisites it still does not work, please let me know.