Poser 6 has a Python script to uncompress the files - you don't need to unzip them with any other program. Within Poser 6 click on Window - Python Scripts to open the Python palette. Click on the Utility Funcs button and then on Uncompress Files. A window pops up with a list of the files that will be uncompressed and you can check Uncompress Geometry files and Delete original files under compression.

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