I had this same problem with mame roms today if I put them in the same folder as LB says to in the
instructions when you try to run a rom it just goes black then back to the LB screen showing the roms,
make sure that you just have LB on it's own in a folder and just direct it to your mame and the roms in
their original folder (separate, don't have them in the LB folder) hope this makes sense, I have no idea
why it won't work when in the same folder.