So I'm building myself a tower to live in on top of one of the rocks near the giant bridge that goes into the undead city.
Its rounded using the triangle pieces (still dont stack, waah!) and has a decent sized floor footprint size the way I've done it. Now, our server just wiped back on the 26th so everyone is basically starting new and I finally got to T3 pieces and went to upgrade my floors. The bottom floor where the entrance door is, directly on top of the foundations on the ground has nothing on it. Each floor is 2 walls high. And it goes up 3 floors above the ground.
I have my various benches and storage on the other floors above. Just furnaces on the bottom floor. When I went to upgrade from T2 to T3 foundations they replaced without issue, at least I thought so. Went back upstairs a bit later and my benches were missing over the pieces that I replaced. Except I'm talking about benches that are like 3 floors above the ground!! It seems that something funky happens when you place and it doesn't just detroy stuff directly on top of the foundation you upgrade, but it shoots directly up and destroys ANYTHING above them, regardless of how high or far away they are.
I dont know if its related to the fact that the upper floors mirror the bottom foundation pattern perfectly, just with ceiling pieces instead of foundation pieces, but multiple floors worth of benches are all gone now, and some of my chests, and my thralls. I never saw a bag get dropped either though its possible I just didn't go back upstairs soon enough to see before it despawned.
Jesus that sucks. All my upgrade materials, thralls, high end weapons. poof.