It may not be the problem you have, but at least one release of DAZ V4 (possibly 4.1 also) has some bad morph data, and combined with the Poser setting Use External Binary Morph Targets, can result in the kind of behavior you are seeing.  The PZ3 files in my case, when I had this problem, were only partly recoverable; deleted the associated binary morph file (*.PMD) and I was at least able to open the scene file again, although all morph dial spins were lost. ps: I've generally found it a lot safer to leave external binary morph targets DISABLED.

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