It don't seems other had this issue, i tried on both chrome and google and the release didn't worked properly, only like 1 out of 15 LMB release actually shot the ball, and the power of the shot didn't reset when the release didn't shoot, so most of the time i had to shot at maximum power by spam clicking which makes the game a whole lot harder to play accurately.
Though the concept is good and beside from that the game is realyl enjoyable, i agree a two player mode would really fit this game