On my installation, they are in ...Poser 4RuntimeAsiaObjMorphs. If you try the wrong body part, you should get a "wrong number of vertices" error. If it's saying it can't read the file, something else is wrong. There is a program called MacConverter (I believe) which you need to use on some Poser files for the Mac but I don't know if obj files fall into that category. I'm assuming that if it was a Mac specific download, you shouldn't need to do anything. Perhaps the obj files are damaged.

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