This is a bit of a functionality error because you can not play the game and use spacebar as a hotkey, even though it is permitted as an option. The reason you can't use it is because once spacebar is selected, it automatically overwrites the natural SPACE=Start game function. My idea is that you could code some bypass that checks for spacebar as a custom hotkey or that just allows for action inputs to also start a match. There are other good ways of doing it but those are some ideas I have.