Well my last contribution to this thread (I'll post findings on 1.30 in a new thread!) is to say that Dege regarding the 3games you can't find demos of:
Ignition: the 3Dfx patch was an add-on to the game so you'd need to find an abandonware/second-hand copy then get the patch. It's great fun so worth getting (Ebay?).
NASCAR: I assume you mean NASCAR Racing 2 as it has a (beta) 3Dfx add-on patch. Again you'll need both the game and the ability to find the patch!
The demos for Ignition and NASCAR Racing 2 don't support 3Dfx.
Boss Rally: Another game with no demo. I have found that with a bit of hacking I can zip the game to about 15MB but that's without the intro video which plays before it goes into 3Dfx mode.
Good news is that I have all three and could supply you with them if you need them! In the short term though I'll just test them as if they work there's no need to send you copies!
Feedback on 1.30 to follow (maybe in a few days).