Tom,
The drain pipe that is cracked is ABS pipe. You want to make sure you use a cement that works for ABS also, and not just PVC.
Here is a thread recently that tells how a person repaired a crack in the ABS gray water holding tank on their TM.
I think I'd try to patch that one before I replaced the pipe.
I agree with Bob on the second leak. It might be the faucet, or it might be a loose nut where the water line attaches to the faucet. Can you take a mirror and a light and look up there and see where it is coming from?
Keith