To configure button mapping, you have to edit the file named gngeorc in gngeo_pepone/conf and add the following line:
p1control A=K281,B=K279,C=K278,D=K280,START=K308,COIN=K306,UP=K273,DOWN=K274,LEFT=K276,RIGHT=K275,MENU=K32
then, you have to suffle the A,B,C,D values as your convenience ;)...