I found a glitch: when on the y2k or 1998 control modes, and you press space arrow keys (not wasd), it will move the tiles by two spaces instead of one. Also the intended behavior of the arrows in these modes is not really documented. I think a more convenient control scheme might be to allow the arrows to either flick move or flick in-place depending on space/another toggle button.
Another minor problem, in the browser the esc key exits fullscreen mode, so it isn't ideal as a "back" button. Maybe add an alternate back button (I like z/x as accept/back)