Magnavox Odyssey 2 rom hacking compatibility with O2em?

[nesrocks]

Has anyone here ever done rom hacking for the odyssey 2 system? The most popular (and only?) O2 emulator seems to change the game's speed to ultra slow if it doesn't recognize the ROM file as a known O2 game. I suspect it does this through a CRC check. I was wondering if anyone knows what's going on.

edit: it turns out the emulator o2em uses a lot of internal hacks for compatibility and it detects the ROM by a crc32 check. So my only option is make it so the rom keeps the crc32 after modification...