I'm trying to construct a cantilevered room. In my case, the structure is a single story with walk-out basement. You enter the house in the front, and it slopes down towards the back exposing the rear basement walls. So the cantilever is actually on Level 1, and it overhangs the walk-out portion of the basement. I'm using Home Designer Pro 2015. Also of note, as instructed by CA, the terrain features are all built on Level 1, the same level as the cantilever.
However I try to do this, the terrain below the cantilever disappears, see attached.
In this example, the overhang was constructed as a room using exterior walls. I've also tried doing this as a deck or balcony, but in those cases, while the terrain below the deck remains in tact, I don't get full walls. I can modify the walls of the deck/balcony to make them full walls, but once I do that, the same thing occurs and the terrain below disappears again.
(Don't worry about structural integrity... in reality, there will be posts supporting the structure so it is not truly cantilevered... I'm just trying to model it and retain open terrain below.)
How do I construct a cantilevered/overhanging room with open terrain below?