Frederick,

There's a note in the Read Me about Poser 8 not supporting the older thumbnails. When we re-architected Poser 8, we removed a code layer that was crippling our ability to optimize the application and expand features in many areas, including the UI. Due to removing this antique layer of code, we had to surrender support for the old previews and the old Poser 4 renderer. The Poser 8 readme explains this as well.

For the betterment of the product in the future, these were two areas we had to give up.

Steve Cooper
Poser Product Manager