The format for the DAT can be found here: http://www.1emulation.com/forums/index.php?showtopic=4912 They are identical to Kawaks. Does Nebula 2.24 have a loader? If so, then you can add newer games to the neogeo.dat (which you'll find in the DAT folder) just like you would add them to ASR.DAT for Kawaks loader. Also, in the settings there is a bar which lets you change how much processing power Nebula can use. Highest is 15 I think and the default is around 10 maybe, I'm not sure since I haven't used Nebula in quite a while. Nebula 2.24 does indeed have a loader, that's what I use. I really wouldn't fiddle too much with the priority setting, since usually anything higher than normal (0 = default) can do more harm than good.