Is "downgrading" to Windows XP an option? For me, Poser 7 works well under XP Pro 64 bit, except sometimes when V4 is in the picture. Othert time V4 is fine.

I develop for Linux in my day job but use Windows frequently. My personal opinion is that XP is not only better than its predecessors but also so far its successor. There's probably a reason why Microsoft extended the time you could buy XP from 2007-12-31 to 2008-06-30 or thereabouts.

Edit: s/it's/its/g, I have to learn to spel.