Derek,
Have a look at the following page:
http://www.nuutbook.com/goods/goods_...ut%20(np-601w)
I can't be 100% certain, but I think this device is based off the same reference design as the Cybook Gen3 (since the physical dimensions are identical, and the buttons positions are the same).
Have a look at how it attaches to the cover. Does it look like the Gen3 might attach in the same fashion?