Mountain Lion and Crossover, well I tried...
I've been using a time limited Demo of "Crossover" on my Mac with Mountain Lion. It's a cheep and simple way to run Windows software. It doesn't involve partioning your disk etc as it doesn't run the Windows Operating System at all but allows you to run PC software directly.
I tried a range of PC Freeware utilities and they all worked so I downloaded the free version of Bryce 6.3 for Windows and installed it.
The installer worked perfectly and Bryce also launched without problems.
The familiar Bryce Splash Screen appeared and then the working screen with the dialogue box for my serial number. But that was as far as I could get as I could not click to enter my serial number so I was stuck.
Actually I never expected it to work but thought I might as well try as it wasn't going to cost me anything.
I've missed Bryce ever since the screen on my previous Mac broke and wasn't worth repairing. I've not felt inclined to buy a second hand Mac either as I've had enough of Macs failing as two have broken at work and my previous Mac had to be replaced twice under guarantee by Apple when both the DVD and hard disk drives failed.