The lack of Tyron's chain is disconcerting. I thought it was a really nice culmination of his story in CoK, showing that his mind really was his greatest weapon. Part of its impact was the lead-up to the chain's reveal, so I'm thinking there's probably no way they'll include it this season. CGI-ing a bunch of burning ship-hulks piled against a chain and being pushed by a river's current is probably a little bit outside the budgetary scope of this adaptation. Also, there's no way that Dagmer *is* Ramsay ... that barely makes sense ... but he sure is playing Ramsay's devil-on-Theon's-shoulder role thus far this season. He seems to be able to control him by giving him an expression that says "That's not Ironborn tough!" I'm guessing they'll drop that little thread. They've had to rush the Rob's camp story a little bit (case in point, Jaime being sprung now) and I suspect they included Karstark as both an impetus for freeing the Kingslayer and as a bit of a nod to book-readers.