From http://www.e-frontier.com/article/articleview/1600/1/582/
*Poser 6 uses a new file format, PMD, to store its external binary morph information. PMD files should be placed into the same directory as the CR2/CRZ files that they supplement. These files are not compatible with earlier versions of Poser, and figures that use PMD files will not display all of their available morphs in other applications.

*There are some bugs that appear in Poser when using Binary Morph Targets (PMDs) with V4 (possibly other figuers, I don't know, but certainly with V4).  By default, when you install Poser 7, "Use Binary Morph Targets" is turned on in Edit->Preferences->Misc tab.  Drill to there, uncheck and hit OK.  For ordinary use of Poser you likely won't notice much difference (I don't).  You need PMD files in order to create separate morph targets that you can give to another person (e.g. I wanted to give someone a no-ears morph, that's part of the process).

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