Just changed my old os from xp 32 to windows 7 x64. Was able to run up to 3 on xp but now I am finding problems now getting even 2 boxes of diablo 3 to run :s.
Same process as old os, have 2 diablo program files, send the .exe of each one to desktop and set to -launch. However when the 2nd one runs, it crashes/doesn't load before it can even get to the login-screen. :S