If you have problems, can you attach these .msh and .msh.blob files? From which format you exported them?
I recommend to use .3ds, .ase. obj for static geometry and only .ase for animated. Actually my program may supports all of those formats: http://assimp.sourceforge.net/main_features_formats.html but support of the most of them untested and probably need fixes.
Train Fever
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