I have two questions: 1) How many ATD's can I hook up to the newest version of the Macbook Pro Retina Display? 2) How am I supposed to Daisy Chain ATD's? Two jacks are on the end of each of the wires, one megasafe and the other thunderbolt. Do I just leave the megasafe one hanging? Because that seems unsafe. Is it possible to use a different cable, or am I supposed to hook the megasafe to one of the jacks on the ATD?