Are blizzard telling you that the software is not Vista compatible ?
I run Redshift 5 on Vista, despite the company telling me it wouldn't work, and that they couldn't help me because it doesn't say "runs on Vista" anywhere on the box.
I found that XP compatibility mode didn't help (though that's the first thing
you should try), but that "run as administrator" fixed the problem.
If neither of those helps, and the software doesn't
say it runs on Vista, then there's not a lot you can do, other than what a lot of us did, and why we're here today, Set up an XP dual-boot on your PC and run your old non-Vista programs from there.
Read the
sticky thread before you start and you'll find a whole load of links that'll guide you if you decide to join us.