Upon first notice from FC on collision issue - upgraded all ceiling tiles from sandstone to stonebrick.
Update came.
Everything vanished from all floors. All placeables with only 3 exceptions out of 20+.
Placeables were left on tiles during the process of replacing. Please note these were the Tier 2, Stonebrick ceiling tiles replacing the sandstone.
Day 2
Hotfix (4/28/18)
Same scenario. Everything gone. This is still on the Stonebrick ceiling tiles.
So upgraded all ceiling tiles to Insulated wood ceiling tiles.
Some of the wedge pieces were soft - you stepped on it and sank, or did the bobble in the air. Destroyed the tile and then replaced.
It is possible that the tiles are inheriting the bug properties from the lower tier tile when doing the standard point and click, to replace with higher Tiered pieces. Painstaking as it is, perhaps should have deleted each one and replaced as I went.
Also, Our server had its daily restart this evening and upon returning, all but 3 crenulations on the rooftops were gone. I had placed them an hour before.
(Your spelling of crenelations is incorrect btw)
We also experience the "no owner’ issue on the various builds.