Also, I wouldn't use the [ and ] keys if I were you. Those keys are kind of special and depending on the keyboard they could be anywhere. Like for my Nordic keyboard my [] keys are on the 8 and 9 keys, they didn't work so I had to just try keys until I found the ones that worked ( nordic keyboards for this game is ´ and å keys). So maybe take like Mouse0 and Mouse1 instead?
Just an idea! Great feel in your game!