It sounds like you have multiple issues going on. First, bleeding is never a result of shedding. Second, it sounds like he has possibly suffered a belly burn. Third, what do you mean a rip in the dry skin? Lastly, a bad shed is typically a sign of humidity levels that are too low.
I would have to say it seems as if the snake was a victim of bad husbandry. What does your friend say about it's condition?
I would get him to a vet asap. Also, begin reading on how to properly care for a ball python. There are a lot of people and threads here that will chime in to help you.
Good luck on taking over his care!