I posted on this in another thread. Are you rendering HD and do you have two-pass checked? If so it will crash (at least for me it did). If you unchecked two-pass it will render without a problem. I believe that it does work for other people so who knows. I reported the error to Sony.
I'm on XP Pro 32-bit as well but I'm not getting crashes on an MainConcept AVC/AAC render.
As much as I'd like to see it, I've never had a bug report window come up :-(
Also, I've got YUV as an AVI render option.
I tried, crashed on 2 pass - ran fine without 2 pass checked - sent the error to sony with the reporting feature - but not the project files - that might have taken quite a while.
Running Vista 64.
V9 64 bit ran Mainconcept AVC/AAC render with no problem on a 4 min project with track motion and other effects. Using various types of media too including MP4 files.
Used standard template Apple iPod 640x480 Video.
This was one of the first things I tested in Pro 9 64bit since this is encoding I use to post youtube videos. Even with applying lower thirds it didn't crash for me.
The Mainconcept AVC/AAC encoding was a problem in Pro 8.1