No, other than making a lot of copies and renaming each to the specific game name you are only going to get the internal MAMEUI screen. I imagine it would have to be re-coded to look for a file (such as default.png or generic.png) in each folder instead. Shouldn't be a big deal but since no one is really responsible(afaik officially)for MAMEUI upkeep, one of the guys who keeps MAMEUI limping along would have to step up to do it. I apologize if I'm off base on this but maybe it'll get you a more solid answer...
Pessimist: Oh, this can't get any worse!
Optimist: Yes, it can!