ok. So whatever I managed to do to fix it came from this thread. Since it didn't resolve immediately upon whatever fix I did, I can't give credit where credit is due, but basically here's the gist of it: Ran update this morning with "Existing Roms Only" turned off, but "Verify Roms" turned on. It Gave me EVERY rom compatable with my MAME version, whether I had it in my roms folder or not... Went back to the configuration tool, turned existing roms only back on, updated the list, and now have the proper roms list... The only thing that I KNOW is different from when I was having trouble is that I took the PC to my in-laws house to continue working on it, as we drove up to visit for the weekend... Geographic location is not likely to be the fix, but for some reason, things just start work properly in this house... May be it is the "ghost" of my wife's grandfather, they always joke around that he likes to play tricks on them... More likely, obviously, is that one of the above pieces of advice fixed my issue, but it wasn't immediate, so I can't say which. So, thanks everyone for your help! Wish I could be more specific.