Ceiling and spiral stair problem

[Gayle Sanders]

Thanks Curt. I should have spotted that "platform edge" myself. Now I see that I can avoid getting a hole in ceiling by using an "open below" room (connected by a non-railing wall to an exterior wall) with invisible walls as needed and platform edge the same material as the platform edge for the "deck" room.

That started me wondering how to change the platform edge of a hole in the ceiling? I made an open below interior room and realized that you can change the material of platform edge of the ceiling hole only if the 2nd floor walls are railing walls (using materials tab for 2nd floor walls). So if the walls are to be invisible, you can make them railing walls and choose the material. If the walls are not invisible and not railing, then the edge is the same material as the wall. Using the eye dropper had a variety of results. Error msg saying that you cannot change the platform edge with eye dropper, try changing walls above or below. Some success with eye dropper changing the edge material, but sometimes it changed both the edge material and some of the railing material. So I would avoid the eye dropper for platform edges.