Recently tested out the demo and so far I'm enjoying it but encountered a game-breaking bug. It's not something I noticed right away and progressively got worse. I had placed my wheat in the furnace, received some bread and continued on with my game. At some point, however, I noticed that I was no longer gaining coal from my furnace but instead got bread. I would also like to mention that my coal started turning to bread halfway through a 40+ stack being created, so it was initially working until something changed. This bread acted bizarrely in that it only stacked up to two pieces at a time unless you threw it all on the ground and proceeded to pick it back up, resulting in normal stacking. Besides that, it seemed to function normally.
From there I destroyed my furnace, and went to go make a new one to see if that fixed the issue and it did not not. Next I tried to throw out everything dealing with bread, wood, and coal in an attempt to build/gather everything from scratch when it came to those materials. I proceeded to cut down a tree and a miracle of nature occurred, it was a bread tree. Every piece of wood I picked up from the tree turned into bread. The same thing occurred with coal rocks, I got wondrous chunks of coal bread. I learned after some experimentation that any item that did not already have an existing stack in my inventory turned into bread upon being picked up (which could explain the initial coal issue, I might have used up my stack as I was making ingots at the time). As a result, it was impossible to continue as I could no longer gather those resources.
As for the chest puzzles, at one point a chest spawned after doing said puzzle and it appeared on a building of mine, making it vanish. Is it possible to make areas where the chest will spawn impossible to be built on? It's nothing major just more of an inconvenience. As a side note, the building that vanished was a mill (the bread apocalypse has me paranoid) and I placed another in the same spot once the chest was gone.