Yeah, I’m using Vista and I know of this feature. I didn’t find a WM2 folder, but I did find an old WM1 folder. Deleted it just in case, but no effect. One interesting thing is the 64-bit version still requires UAC to run, while the 32-bit version does not. I guess, simply put, are you sure you have the right version of the 64-bit executable in that installer? I can’t confirm the version anywhere. The executable’s metadata for both executables reads 2.0.0.0, and the About dialog has no version information (aside from the major version).
But, right now, I have no other information to report. 32-bit version works (though I haven’t tried to build a world with it yet). 64-bit is unable to run due to the world.ini error.
EDIT:
Okay. So I used Vista’s Shadow Copy ability to restore some of the stuff I lost when I reinstalled. The examples folder and my macros. Anyways, I also found a world.ini file in there, so I restored it to World Machine’s Program Files directory to see if it would work with the 64-bit client. Now, when I run it, it doesn’t complain about the INI file (apparently, it still expects it to exist in the Program Files folder), but asks me for my registration code. When I enter it, it says, “This code is for the Professional Edition. Please contact (…) for the correct software package.” Well, last I checked, the 64-bit version WAS a part of the Professional Edition, and exclusive to it. So, whats happening here?