it all has to do with keeping up, and you have to have been there from the beginning in terms of neogeo games first of all with mame, you'd have to add the games into the source code yourself in order to play them second, they won't work because as time goes on, ppl want the games to be more like how they worked on the original machine that it was played on in order for it to be like the real thing (the point of emulation), therefore you hear more and more about newer neogeo rom sets that are encrypted being dumped therefore, since they are encrypted, you would need decryption code being programmed into the source code of the emulator so here is some info 1) neoragex is not open source and it does not boot encrypted rom sets 2) kawaks and nebula are not open source