Well my setup is a hybrid of both Xpadder and the MAME settings. I use regular joystick inputs for these buttons, and mine is working without Xpadder, so I can assure you this works without any extra settings. A couple of thoughts here: is your MAME.ini set to read only? Immediately after mapping and it says it's mapped, enter the tab menu and look again. Are they still correctly mapped? If so, do they work? Or are your settings not being applied when you exit the game and reenter it? This sounds more and more like a problem with MAME itself, in which case I owe you an apology, Tempest. My bad. :-)