I noticed that when I placed a kiln in a way that the exterior part of it would touch the exterior part of a smelter, the entire floor level of the metalworks would just disappear, and it's not only visual: you can't access the metalworks menu anymore. I hope the images make the matter more understandable... I tried placing, removing the kiln a few times and came to the conclusion that it's the "touching" that gives problems. A save is attached (ok, I can't remember if the 44 is the correct one, but the 004 is the same game, only a few days after. And during a foreign invasion... during which it crashed...)
I don't know, I went back to the stable branch since the "icon bug" would make it quite difficult/annoying to manage a bit of things...
