Ages ago I made a video showing the setrotation and setposition commands. I had no problems back at the time, but now I get this: https://steamcommunity.com/sharedfiles/filedetails/?id=2288142789 Is there a optimisation that caused this, it happens if if I do setrotation to the exact same angle the building was before, so it's even more confusing. The groody bit is you can place blocks, they are not always visible.... and sometimes when you re-load, the blocks are actually placed, but may be on the other side of the wall you were facing.