Scripts

1. Create a Fortress.
2. Destroy the Fortress.
3. Place a Necropolis in its place.
Have you tried that?

Point 2 doesn't work. The same thing happens: the object is indestructible. The same error appears in the console.

Added after 31 seconds
Although it is definitely placed by a script.

Added after 1 minute
CreateDwelling("ddd", TOWN_FORTRESS, 1, 0, 32, 3, 0, 90)

RazeBuilding("ddd")
CreateDwelling("dddnew", TOWN_NECROMANCY, 1, 0, 32, 4, 0, 90)