I didn't spend a whole lot of time this week on the model, but did manage to get the roofs and towers around the wall perimeter finished. This was a fairly straight forward task. It starts by gluing in place a small tower, followed by a long roof, then another tower and so on. Total time now spent on the model: about 14+ hours. Here's a couple of progress photos and some tips. Enjoy!
Getting the roofs to hunker down into a good fit is covered below.
I used a black felt-tip marker cover the exposed edges of all the roof sections as well as some other areas around the structure.