I had an issue where I built a two walls and put a double doors in it to let them through, this was part of the gatehouse I built. All of a sudden when the second wall went up my Hearthlings stopped working on the other sections of the wall, since the scaffolding was on the outside of the wall. I noticed later that when I tried to order an attack team against those filthy goblins that they too refused to go through the gatehouse.
When I put down ladders on both side of the wall both construction completed and my units went on their Glorious Crusade.
