What I want to know is, that after beating the main quest, that nordic chick (forgot her name) tells you not to go further down the path, and there are other times as well that it is heavily hinted that mora will talk to you yet again. anybody experienced anything?

I quess we meet him again in future dlc. Havent talked him after completed MQ.

I was wondering this too, Frea didn't seem too impressed when I read another black book after the MQ. It would make sense that there was some sort of negative consequences for gaining all the powers from the books or at least some dialogue with mora where he claims to own you (although I guess he has said this a couple times).