I really did try to build the Prison Tower according to the instructions but the front doorway begged for something heavier - a shelter for the guards, perhaps - which led to the addition of the dragon skull atop the capstones.

Also, I had tried the blocky crenellations (left) and decided to make my own version with three of the small bricks and a trim piece (right). I think the slim, streamlined effect is more appropriate to a light building like this.

Here's my version of the Prison Tower - if you looked at the Hirst plans and prototype, you'll notice even my stairs are different. That was an accident... But notice how well the guard is sheltered from the elements under the imposing doorway, and how the crenellations look like jagged teeth pointing wickedly at the sky!

I am very pleased with the cell door on the upper level... it is a paper door from the Hirst .pdf files, available from the Building Plans page. I cut out the "window" area and used real wire as the bars. The door actually opens, because between the paper layers is sandwiched a thin layer of fabric, which extends where the hinges would be, and is glued between two 1"x½"x¼" blocks instead of the normal 1"x½"x½" block.

(Left) You can see inside the cell - there's straw more for easy clean-up than prisoner comfort, a few blood stains, and the skeletal remains of an unfortunate inmate. (Right) Here's a good shot of the rear, showing the altered stairs.