I seem to remember that this sort of behaviour can happen if you are using external geometry and the rsr in the geometry folder gets corrupted. The fix for that is to delete the rsr (the one in the geometry folder NOT the one in the library sub-folder ), Poser will build a new one next time the thing is loaded. If that does not work perhaps there is a problem with the *.obj file. Try importing it directly via "File>Import>Wavefront OBJ", If that works it's probably OK, if not get on to the supplyer.