Did you get the .EXE or the .SIT from DAZ when you downloaded - most often when I get that message it's a Mac file, with several tens of bytes of MAc info at the start. For the PZ2 files, open in Notedpad (the XP version is fine for most Poser files - it doesn't have the 9x version's size limit) and remove the strange characters up to the { at the end of the first line. Macs put their thumbnails elsewhere (resource fork says a hazy memory) which is why you don't have any RSR/PNG previews. Of course you could just redownload, choosing the EXE this time, if you haven't run out of time or tries - I'd certainly recommend asking for a reset so you can get the proper file for future use.