Here's a ton of info on the file formats used by OP2 and internal structures used in memory. Basically just notes I took while going through the exe. Not all of it was written in notepad. Some is either saved in another format or was written down on paper. If there is a section you feel is missing or incomplete, it wouldn't hurt to ask about it. There are many things I was either too lazy to figure out, or just plain didn't have the time to look into. Or maybe it's just because it didn't seem useful at the time. If you have any extra info on it, please share.
Hopefully, what's in those files is mostly up to date, but there is too much for me to really go through and double check. There are also a few things probably still scattered through there that you shouldn't know, but I'll leave you to find them.
Oh, and don't bother asking about the cheats. I'm not telling anyone anything about them. I've removed most of the info on them for a reason.
Go
here.