That would work if all I wanted was Mac portable. I've got multiple versions of MAME, and multiple attract modes already working for PC, and I want to add Mac compatibility. Pretty sure it's feasible, Macs support indirect file references. It will take moving the config folder, running the program with a script that allows command line options that tell it to point to the local folder.
I don't really need it, but at this point I'm just stubborn.