Hey,
Amazing work!
I love retro ports of modern games:D
one thing I was wondering though, did you realise you went over the 32k mark with 1.5?
I made an eprom cart a while back thinking the vectrex only used 2732 eproms, so I havent got the pins for a 2764:(
veccy bird 1.5 sure gives strange results when you only burn the first 32k haha.
I've seen a couple of bank-switch style eprom cart projects which only support 32k roms too, so if high compatibility is something youre aiming for it's a good thing to keep in mind:)
Have you made any other games? I'd be keen to check them out.. if theyre under 32k:P
James