I have a new train set that we purchased with 2 DCC equipped engines, along with an expansion track pack.  It came with 1 controller.  I have 2 children and they would both like a controller to controller their own train.
1) Can this be done with DCC?
2) If so, what is the model number of the additional controller I need to purchase so that I can have 2 controllers.
3) I am assuming it would be straight forward to hook up the 2 controllers, but if not, is there something I should know about before doing this?

Secondly, I want to hook up an automatic reverse loop module, but some books I read say you need to have some Gap Tracks?
1) Does this come in the Easy Track?
2) What is the model number for this?
3) Where do these gaps need to be (I am assuming right after the switch or something.


Thanks for your help,
Tom