Hello. I have an external HD (350G with 290G used) plugged into the back of a new T/Capsule. I have a new MBP with no data on its HD and my daughter has a new MPB with no data on its HD. Is it poss to always save to the external HD wirelessly and have the TC back up that HD. Also, all my itunes music and films are on the ext HD. Can my daughter and I play, buy content to/from it without it saving to our respective HD's.