I did a quick playthrough the towers to test (I didn't check the main building out since I have to run out) but there are a few problems I've never seen before.
The first one I ran into was the 2 regular guards (not the mages) outside the earth tower would for some reason would stop patrolling to the left of the earth tower entrance outside the tower. Not a big deal, a quicksave/quickload gets them moving again.
Didn't have another problem until the Air tower, and this one was frustrating. For some reason, the air mage in the front (the leader of the pair patrolling that is) of the 2 mages that patrol the first large room would once past the elevator on the bottom part of the room, would for some reason upon quick loading levitate in the air just below the upper ring and reverse direction, until he made it back to the stairs and gets stuck in the corner. This one is sort of game breaking, as if you don't have a save to revert to prior to his levitation then he will repeatedly pull this stunt making it VERY hard to get past him if you can at all.
Didn't have any missing elevators in the Air tower. I hadn't had any missing prior though, but we all know it's a fairly uncommon bug.
I did find a new problem though. I decided to take the secondary exit from the air tower into the central keep instead of going back down and apparently now the door to the main keep is missing. I have no idea how that happened. It sure helps the guards out though!
The good news is that the mage in the Fire tower patrols now. The bad news is the mage on the level below pulls the same levitation trick under the stairs and immediately gets stuck. This actually works out immensely in my favor, but it shouldn't happen.
I made saves at the air tower floating mage, the missing door, and the fire tower floating mage and tossed them into a zip file. You can take a look here if you like: https://docs.google.com/file/d/0B7u9...it?usp=sharing