I noticed something while locking at the ESC thats noted in the BOM.
Hobbyking state that the ESC's have 6V BEC output, and if you connect them to the Cape board, you will send 6V into the 5V part of the Cape.
Shouldnt the Red(6V output) wire from the ESC been cut, or the mid pin of the headers on the cape?
I've read on some forums that systems with several ESC(Ie. Quadcopters) with BEC circuits sometimes conflict, and they end up with destroying the ESC because the BEC circuit doesn't support to be parallel connected with other BEC's.