There's a rominfo.dat within CPS2 and NgePSP you can check the right name files.. Like MVC that's supposed to be Mvsc (suggest you renamed it to mvscu). I don't find cps2 games too difficult to find since I can get them worked except 19xx and SSFT.
But yes, it's rather difficult to find playable Neo Geo roms. There's a suggestion that you'd better download mame version of Neo Geo. I have not try it myself yet..
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