MH12,
It seems as you and I are looking for the same solution. I am also using a J-Pac to encode the button and joystick inputs from my cabinet. So, where Player #1 joystick uses the UP, DOWN, LEFT, and RIGHT keyboard keys to navigate; Player #2 joystick is set to use e.g. the D, R, G, & C keys for movement. Therefore, if the UP & DOWN keys scrolls through the game list for player #1, we would want to be able to scroll through the game list with R & C keys for player #2. I am only looking for this capability in the Mala Frontend Menu section where you scroll/navigate through the lists of emulators and games.
I see where Mala allows dual control in the 'JoyStick/GamePad' setup but, I don't see that ability under the 'Keyboard' setup. Please correct me if I am wrong.