I just wanna say that I'm not 100% sure that this is a bug, but to me it does seem like one.
(If the photo aint showing up it's because of imgur.com being down or something. Link to pic: http://i.imgur.com/LRq3dh.jpg
So here you can see that the ramp (right) to access the bridge (left) is missplaced even after getting the message about the walls being completed..
(It's the same on the opposite side of the town as well)
Also, cannot move the treant away from the bridge :P tho maybe I could just put him in a army then put him back into the town, but still thought I'd let you know.
So, if this is a bug I hope there's a way to fix it ^^
If it's not a bug, then please do tell me how I connect the ramp to the bridge or the wall