With apologies for starting so many threads at once. I've been doing my reading (when I even have time) on my bus commute, only able to make margin notes, and this is the first chance I've had to get it all typed in here!

First, the signature on James' letter to Catherine in Ch. 27: "Who ever am, &c." What does that mean?

In Ch. 28, we are told, "By some means or other she must have had the misfortune to offend him. Eleanor wished to spare her from so painful a notion but Catherine could not believe it possible that any injury or any misfortune could provoke such ill-will against a person not connected, or, at least, not supposed to be connected with it." I don't follow this. What's the "it" referred to at the end of the sentence?