I know WHAT happens at least. The vertex order has been fubared. That happens with some programs. UVMapper (at least pro, can't remember if it can do it in the free version as well) has an option to reverse the vertex oder, that can sometimes fix it. But not always, unfortunately. Try importing/exporting all the non-morphing bits (the things that explode) like you did with the belt loop. If all goes well, they'll be reordered as well, and in that case the end result might be a morph that works.

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You just can't put the words "Poserites" and "happy" in the same sentence - didn't you know that? LaurieA
  Using Poser since 2002. Currently at Version 11.1 - Win 10.