Minor Tile designators don't affect walls with large objects next to them

[pitaden]

I decided to build an incredibly ugly shuttle as a construction worker. It was going fine, up until I decided to start placing windows and airlocks. When a window/airlock was placed next to a wall, the wall reset to its default appearance. Trying to use the tile designator on the wall again didn't change its appearance.

To recreate:
Build two walls, with a one-tile gap between them
Paint both walls with a tile designator
Place either an airlock or a window between the two walls
The walls should reset and become unpaintable.