Hola! I'm gonna help a brotha out (I had this problem before when I was first setting up my cab) Assuming that everything is setup in the setup wizard correctly, what's going on is the version of mame you are using doesn't support the rom files you have. It will show in GameEx that you have the game, and it will try to open it through Mame, but will error out and will return to the front end. The best way to solve this - and it will take a little bit of "elbow grease", is to download one or two "alternative" (older/different) versions of mame. The one I use for Killer Instinct is 0.103 and I'm not too sure about Street Fighter III 2nd Impact, but with 3rd strike, v0.146 works well. After downloading and setting up the games through the other versions of mame, you will have to set the other versions of mame as emulators in GameEx setup wizard and then use the Mame Mapping Magician to "tell" GameEx which rom files to open with which version of mame. It should work well after that - Oh, and if the name of the rom file is a little different....e.g. (hypothetically) if kinst.zip doesn't work through the different version of mame, but kinstua.zip does, you will have to use the setup wizard to filter out the kinst.zip, and then add in (include) the kinstua.zip and then update the list in GameEx. Lol, it really is an easy thing to do - just can take time depending on how many games ya want working that doesn't work in the "main" version of mame you wish to use. To help your search a little for the different versions of mame, this link should take ya where ya need to go: http://www.progettosnaps.net/mameui_en Hope this helps!! LC