Thanks for the info possessed!! You're totally right, I've made a test and what's before the _ does not matter... The _p1.rom is directly related to the NGX's detection process. So, I guess I don't have the correct _p1.rom for ss5 and kof2002. I need some tips here to find those, please. Thanks as well to Agozer! (sorry I did not get it at first). It's ok. If a game isn't listed in the gamelist, The P1's internal name *almost always* defines the gamelist name.