Ok, here's what's going on. The settings folder and files therein are created on the fly, they are not part of the installation so the uninstaller can't remove them. If you delete the settings folder, everything will go back to defaults when you fly the next time, joystick settings, keymaps, preferences, etc. It sounds like you just need to remap the squad highlight function and you'll be fine.
------------------
Doug "Pyro" Balmos
HiTech Creations
"I say old boy, why don't you shut up and die like a man?"