Are you sure that Vue is configured for the correct version of Poser that the pz3 files were created with?  If you have a pz3 and it was made using Poser 6, but Vue is configured for Poser 7 (or used Poser 7, vue configured for Poser 6), problems will happen.  

I use both Poser 6 (90% of the time) and Poser 7.  It's a pain, but you need to keep track of what version Poser you used and make sure Vue is setup correctly. 

I use the Mil cat and horse in a lot of pictures - never had a problem...

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