You don't move, that's the purpose of the game, about enemies not coming in, I don't know why, more than 10 people tested and none had this error, did you provide space to start the game?
Oh! No, I didn't hit the spacebar. I completely missed that. Since every other button is activated by shooting on it, I assumed the middle left button was the "play" button but besides making all buttons disappear it didn't seem to do anything else.