@zetof I tried that but the hotkey to the Mame GUI is blank so the keyboard hotkey does not work either.
My controller still works overall, I just have no way of reaching the settings menu for the Mame core now.

Hello everyone,
Fairly new recalbox user her and working on an arcade box project with my daughter. I messed up in the Mame2003 emulator while trying to fix button mapping. I was changing the GUI hotkey but after it waited for the new combination it wouldn't accept any key presses. The emulator backed out to the system/core menu with that hotkey still blank. I cannot find a way to remap this hotkey as I need to either find the info/config for this, or use the hotkey that is no longer mapped.
I am using a PS3 controller
Dragon blaze 6.1 build
For x86_64 machine.
I can't remote in using the ip method and have my install booting off of a thumb drive with the roms mounted to a removable data drive.
Any help would be greatly appreciated.
Sorry if this has been answered before but I could not find it on here with a search.