Ball is moving too fast. I tried two different browsers and the ball moves in different speed. I assume you didn't multiply the amount of translation by Time.deltaTime? (If so, I suggest you fix it and re-upload the fixed version. That falls under the category of "game breaking bug")
Game files are not locked so if you discover a major issue with your game file it is possible to change this afterwards, just make sure you make a submission before the deadline. This is only for game-breaking issues, don't use this feature to otherwise update your game before the rating period is over.
Anyway, that's a great concept. Simple and creative!