New Demul user troubleshooting

I just got Demul and am trying to figure out how to run roms on it. I keep getting the error message: unable to find 'epr-21577e.bin' in romset 'NAOMI'. However, I found a bios bundle that has that file in it and yet I still continue to get that message(the bios is placed in the same folder where Demul looks for the roms) Any idea what I'm not getting right here?

Ok, it's almost 2 years later since my first post here(I gave up during that time lol) I now have a new machine. It's a Lenovo desktop with dual core. Each core runs at 3 GHZ and the total RAM is 4 GB. I also found a Demul rom and bios bundle(it's a torrent so I selected only the game roms I wanted and all the bios files it had) and am running the most current version of Demul. When I go to run any of the roms, there is a couple of seconds pause where it appears it will run and then an error message appears saying it's unable to load rom(I'm trying to run the Naomi roms I that came in the bundle)

Is there a config issue that prevents them from running? It can't be missing or misnamed files because the error message would come up naming the missing files so the roms I' trying to run are complete(I verified this by trying to run a rom for which there was no romset in the directory). This could very well be a video card specs or driver issue because my PC specs seem plenty enough to run the games. Any thoughts on this? This emulator is almost as frustration to me as the current Sega Saturn ones.