found that if you build near water the game tends to bug out the buildings and try to do ladders like so this will result in the building never being completed. no clue if this has been reported or not. though with how easy it is to get to happen guessing it is likely to have been reported.
On a side note, if you build a building next to a cliff and the roof overlaps the building will freak out on that point and stop until you mine out the overlap area. though if you where to do the same with another building it results in this overlapping voxel glitch which just looks strange.
Placing items next to cliffs can also result in those ghost ladders. Sometimes even restoring the goblin camp does, if it was close to the edge. But hopefully the building rework should solve these issues eventually.
That’s expected if he gets hungry or sleepy, since the camp is so far away. But eventually someone should come and finish the restoration, unless everyone’s super busy. There’s a bug that they leave a hole where the dirt pile was, though.