I'm getting that as well - when you press B to redefine an input ( eg Player 1 button 1 ), then press a button ( eg A ) , nothing happens ( it doesn't seem to come out of this state until you press about 10+ buttons, and then of course it's a right mess regarding the button to press ).
Thanks Mal, that's the exact behavior I'm getting. Now I know there's not something unique to just my Dingoo or anything.
i'm using an original dingoo digital paw'ed dingoo with the 1.2 native firmware. i can not remap any buttons either. i am having the same problem as the two of you. even if it did work, the buttons are not listed in the emu as "X, Y, A, B" so even if it did work i have no idea which is the button i want to remap.
after using "input (this game)" option the buttons to have been remapped but i have no idea what i did. i'm playing Contra and now i have to press X+Y+A+B to shoot and just B to jump.