Hi Mehcore!
I’m in the same situation as you – I just "upgraded" to Vista 64 (Home Premium) and just when I thought I had got most everything working the way it was supposed to, the bomb dropped – my development environment (Visual C++ 6) doesn’t work properly in Vista, and I’m not sure what to do yet. Dual-boot would be a huge hassle, but I might not have a choice.
The hardware ID, in theory, should be the same in both OS’es.
Try it, let me know what you get.
///Leif