Very cool project, just starting to play around with it...
One thing I noticed is I don't seem to be able to delete structures, maybe I'm missing it.
There's no overlay to move or delete for walls, slabs, etc...
Doors do have the overlay, but attempting to move a door crashed the app (go back or reload the editor)
There's a delete option in the toolbar, I toggled that on, but it also doesn't work.
Feel free to close if this is WIP, I know it's still early days.