GryphonKlaw, Thanks for the response. I appreciate your help. I have all four V roms in the zip file (272-v1, 272-v2, 272-v1d, 272-v2d) but only 272-v1 and 272-v2 in the DAT. I would find this to be more of a problem if 272-v1 and 272-v2 didn't match James' CRCs. It would seem to me that either this set should be working, or Nebula just can't play encrypted games (at which point I guess I can compile MAME) I actually did try Kawaks, but with the same result. =[ I guess my instinct would be to get another set of ROMS, but it seems so odd that these won't run even with the correct file sizes and CRCs. I should probably try to either find a decrypted set when I get my cable hooked up (on 56k at the moment =\) or just compile MAME and run it in that. What it boils down to is that I have to wait to get my cable hooked up to find another set and I'm too lazy to compile MAME if I'm not sure it's going to work in that emulator. So, to answer my own question, I should probably just stop wasting your time and compile MAME to see if it works. Thanks everyone, and any further insights would be appreciated if there's something blaringly obvious that I'm overlooking (which I don't doubt).