I ecnountered this bug today: The skirmish match options menu is bugged. All the maps seem to be gone, and none of the options except for "Back" seems to do anything (screenshot here). I didn't modify the game files and the game ran fine a couple of days ago.
I'll probably just reinstall it, but I'd be curious whether someone knows what could have caused this.
I'm running the disc version of RA3 with the latest patch on Windows 7 Ultimate 64 bit.