Just got it working in WinUAE.
First off....great job!
Things I noticed (may have already been mentioned).
I don't think it should stay on the title screen forever, if the user doesn't press a button within a minute then either auto start (or even better), run a demo-loop.
The player characters don't seem to hold the weapons correctly.
I think the palette changes on the enemy characters isn't right (when the walk through a door and into the main play-area).
The aspect-ratio is a little different to the arcades but it still looks really nice.
The sound was a bit scratchy but that could have been a WinUAE thing.
Keep up the good work!