@t3kg33k it could be done, but:
1: there'd be no separation of systems. Having them all in one folder, the front-end has no way to determine what's a SNES game and what's a Megadrive game. So you've just got one big "everything" folder with all your games in it. Suppose you could make custom collections for each system, but you're still sorting them manually and at that point you may as well just sort them proper into folders anyway.
2: it's going to be a lot of manual busywork, setting the specific emulator for each rom because, at most, maybe two or three systems (Sega CD, Megadrive, and Master System for example) will use the same "default" emulator, and everything else will have to be set custom.
