I was stuck on L7 until I realized the problem... You can move the starting position, not just the angle that I had thought. After being frustrated with multiple attempts to beat it based on angle only I gave up and decided to read the directions to see if I could move the start position at all and then I read that you could... So I am 100% sure that anyone who is stuck on L7 probably didn't know you can adjust the starting position with the up and down arrow keys.