You can see in the CAD software snaps in the OP that there is a file they were working on for the USB Thumb called Heatsink.  I would assume Barntech is working on a solution for a heatsink for the 8 chips board as well.  Interested to see what he and his team come up with.

Regarding firmware development on Cgminer.  This is a great piece of open source software and I am confident that Barntech will be able to get a really solid firmware created in a short amount of time (If he has not already simulated his boards).  I saw posts that he may even program a GUI to make integration even easier for those who may not know USB protocols.

If at anytime Barntech needs additional PIC firmware coding, Cgminer API, or GUI support.  He can feel free to send me source files and I will share everything in this thread.  I am not sure how open source Barntech is but rest assured it would be worthless to steal source code for hardware I don't have 

Regards