Thats  a good idea Switch to a windows version of Bryce as I don't think Mountain Lion is Compatible. Snow leopard is ok But this machine itself has had more problems than a windows pc and for the money it cost thats not really good enough. I am not sure about Mountain Lion it maybe compatible but probably not. Bryce 7 pro is still free on Daz3d for a while So I would download it for windows soon before they change their mind. 

Good Luck 

Karl