The grunts sounds are from the human vocalization pack btw Edit:I am not really sure but it sounds alot like the grunts from the pack. The pack is free and it has tons of both female and male vocals
You could add a score decrease based on time, so for each second it decreases your score by 1 or so. This way, the player is punished for getting hit by cars and not evading obstacles correctly, as the character will fall and get up (which takes time and thus removes some of your score).
