If it's a PZ3 why not simply try editing it (with wordpad os similar) to "appear" like Poser 5 - with that I mean simply opening it in the text editor and changing the "Version = 6" to "version = 5" Works in Poser at least, I always edit my freebie-files to show 4.01 instead of 6...

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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.