Thanks so much for this. This is precisely the sort of nitty-gritty I was wondering about. I appreciate your time and your efforts in the emulation scene a lot.
To be clear, the stuff I posted about isn't generally important for running games. Getting the whole commercial game library running is a goal that was more or less passed a long time ago (excluding stuff that depends on obscure peripherals anyway). The things in that list are obstacles to approaching the platonic ideal of perfect emulation and are sometimes problems for things like verifying tool assisted speedruns or catching bugs in homebrew development.
IIRC this game shipped with broken EEPROM code so it's a bit unclear if this is actually emulated incorrectly. Ares is really in great shape these days
I do have a couple minor open compat bugs in BlastEm (my public issue tracker is sadly not up to date...), but I believe these are just normal bugs and not "we don't understand how this actually works" kind of things.
EDIT:
> Last I looked into it, even Overdrive 2 was emulated pretty well...
Yes. In BlastEm there's a one-line glitch in one of the scenes I haven't managed to figure out. In Ares, there's a single effect that doesn't work (border dissolve after the "arcade" scene) and a 1-line glitch in the arcade scene. Both are only visible if you have overscan enabled.
That is outstanding work. I can practically smell a physical MegaDrive burning somewhere every time I watch video of Overdrive 2 running on real hardware. My deepest respect and thanks for the work you've done on BlastEm!
I looked but couldn't find much information on remaining games that still have emulation issues. This was about all I found: https://ares-emu.net/compatibility/21?status=3000
Last I looked into it, even Overdrive 2 was emulated pretty well...