Whenever a new version of MAME comes out, I wipe the folder (except roms) and unzip the new binaries. SDL we're kind of getting into "I don't know" territory. I've never gotten controllers to work right with MAME so I've done lots of tinkering with my version. Assuming I got everything right (that's a big "if" plus I'm not sure how to tell), I should be using the SDL supplied by the brew package manager. Aside from controllers, mame runs fine and so does my Naomi emulator that also uses SDL.