About 2 hours ago a house dropped and the timer has only just run out. Left behind is a painting (which was underneath the house sign), a floating water trough and a floating 'stew', presumably from the heritage item. I know a 15x15 will fit here, as that was the size of the previous house. However, whenever I try to place a house I'm told the terrain is invalid and/or there are items blocking. Would any of those be the cause?