So after writing a 2000-word epic, I've still got stuff to explain :l Anyway, for the sake of comparing REV02 versions, I've created branches of the S2 Git disassembly that produce bit-perfect binaries of the Mega Play and Sonic Classics builds. Going by its wiki page, the Mega Play version of S2 was nowhere near as heavily-modified as S1. Still, when I actually got around to disassembling it, it was anything but simple: the Sega screen and options menu were ripped out, a massive blob of arcade-interfacing code was added and hooked into various parts of the game, and even a new bug was introduced. The Sonic Classics disassembly, I made years ago. It's a pretty straight-up REV02 build, besides the bugs and having no checksum routine. It also had some RAM rearrangements.
