DraStic

Using 8BitDo's NES30 controller, yet when I go into Change Options > External Controller, the only option available is "Show Maapping" with no way to change the buttons to better fit the DS layout. (For the uninformed, the NES30 uses the same button layout as the DS/SNES). How can I fix this?

The very first option in the external controller settings should allow you to select a different mapping slot. Afterwards you should be able to do a custom mapping.