thunderstone..you scared the wits out of me with that subject line! :-p lol.. :-P just kidding. 

i had to switch to win 7 when i got my new laptop..it isn't a probs.just don't forget to save your content files..obps, and mats etc. I've got 7.0 and 7.1..or whatever is the latest version of bryce.

have fun... 

cheers