Installation looks good. Did you check the potentiometer to regulate the LCD contrast? Make sure it's not that.
If that's working well, I'd try to get it first working with a game without injecting keys. Don't install the wires and try to run a Team Avalaunch game. If that works, then you are on the good track.
If that's working well, I'd try to get it first working with a game without injecting keys. Don't install the wires and try to run a Team Avalaunch game. If that works, then you are on the good track.