Hello !
You can easily achieve that by using the basic shape feature of the build mode, setting the sprite preview to enabled and the corrects regions ids on the free mode/restricted mode options (depending on which one you use).
If you still struggle to make it work, please let me know !
I did that and there isn't a preview when it's larger? I triple-checked that preview was enabled. I even tried it in a fresh file with nothing but this added to it. It also allows for placing a portion of the tiles into the banned region. It only blocks it if the player is actively standing in the banned region but doesn't block it if they are right on the edge. This causes the option for a majority of the item being placed in an area that should be off limits.
