If you want to get the badge, you must destroy all cars then click off the screen. It will send you back to the title screen and should get you the badge.
The hit detection is sorta off, sometimes when at high velocity in a ball you could go right through balloons. And when riding the rocket at the same speed you could hit something. Really ruins the run but not the fun.
Do you mind adding some kind of quality setting, my game gets really low frames during transitions sometimes. (BTW, I was ADDICTED to Run 2, it was like a drug.)
To the guys that don't think the game saves, then just go back to the main menu then re-enter your last profile. This will save your game so you won't give up on this game that has potential to be one of the Game of the Year nominees.
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It's in the right-click menu. I don't know if it will actually help; I think the problem may lie elsewhere. (I'm working on it.)