Well, I called Sony tech support. You need to pay $29.95 for help with a single issue. That sounded fair to me, so I gave them my credit card number.
The lady, Liz, was super nice and asked for a rough idea of the problem. When I told her, she stopped me and said, "We can't support anything but Windows... even if it's installed via Bootcamp on Windows."
Then, she made sure to tell me that my credit card would be credited if a charge had actually gone through.
But, no other offer of help or recourse. Wow! I've been strong customer for at least 6 years, paid upgrades the whole time... and we can't even discuss this? You're telling me there isn't a single tech person there who could look into it with me? Ouch... then I guess I'll depart Sony Vegas customerhood with a tip for Sony to read this book:
Thanks Corsedesign, you got me on the right track. I went back and verified the versions of EVERYTHING. yes, Snow Leopard, Bootcamp 3.0... but then I noticed when booting into Window 7 that there was an "N" after the Windows 7 name. "Windows 7 N".
After some digging, I found that the European Union forced Microsoft to offer a version of Windows that does not come bundled with Windows Media Player and associated assets. Not sure how, but this is what my IT guy gave me!
Yes, and the Installer error was then caused by Vegas needing to connect with a bunch of "associated assets" that didn't exist in that version... Still, not great error handling but I can see how the developers hadn't thought that could happen...