Hi Thor, I took a close look at this polygon output, and I could not find any problems with it, as best as I can tell the polygon output is properly formed.

Unfortunately, it is not really an easy task to code a properly working n-sided polygon triangulator. It is very easy for programs to have bugs in this area, where triangles "leak" outside the boundaries.

I'm pretty certain that is what you have run into here - Carrara and Kerkythea seem to have some bugs in their handling of complex n-sided polygons, while Blender and Silo are stronger in this area and process it correctly.

This is actually a rather common problem. This is the reason why MoI has a setting so you can output to "quads and triangles" or "triangles only" instead of ngons. If your target program does not handle complex many-sided polygons well, then you can have MoI break it up into quads and triangles which will then work properly with the target program.

If you like, you may want to send that .obj file to the authors of Carrara and Kerkythea as a bug report.

- Michael