I've been having it work using both, but... I do odd things to my system. Basically, if you have problems, decide which to run (I'd probably suggest 64-bit if you're running that system and don't have a solid reason why you need the 32-bit Java) and try it with just that. If it works, great. If, at that point, you want to load the other and see if it still works, at that point you have a single item you're testing at a time. But I think what we've found is that the problem is something about your installation, not mafia itself or anything that we can directly help you with...