needs alot more work
first off, when those 3 yellow arrows go by, theres white showing on the bottem of the screen. second, i think it should be then than using the mouse. maybe have player 1 push the shift key when he sees the yellow car, and then player 2 presses the enter when he sees the car. also, your rules was not writin very well. i couldnt understand it at all until i looked at it closely. and maybe have some tricks, like have a car that is half yellow, half white, so when it first comes up, it may be the yellow car, or it may not. make it alot more deep with some tricks to keep them on their toes.
also, right after the 4th car passes, a blue car flashes for a second on the bottem road, you may want to fix that. just work on it somemore, and it could be a very well made flash