A lot of the really old MAT poses, also, were Subdividing Materials, that actually swapped out geometries in some fashion. I remember when Anton first released MAT poses, it would completely frag some things. Could be the case with some of the MAT poses you're having issues with.

Or, as is the case with MOST issues in Poser, it could be that you've pissed off some ancient God or Goddess and you accidentally appeased him or her through some action.

... Or a bug. I suppose a bug might be possible. My bet's on the Gods theory, though.

Kreations By Khrys