So I've build this beauty.
Not that I was going to build my own Flat Lagoon City replica, but !!! :-(

1) it costs A LOT. But okay, 1k materials is gatherable.
(why? proportional sized other big buildings costs 20-100x less)

2) is this just me or I can't build normally on this platform except few buildings:
Small Shack (yey...) and Outposts S-III, S-IV & S-V.
But really buildable is only Small Shack. Big ones are just being placed too high, so its stairs unreachable.
Flat Lagoon has some different houses on its platform, why we cant (:

3) Interior category is unavailable - it says, must be built (surprise) inside. But I cant build houses on the platform! :-D
Exterior - also no - too close to another building.
Walls, gates, turrets - same.

Okay, I can build walls and gates around the platform and a bunch of Small Shacks on it but..this is insane solution.

Any workarounds, please?
Thanks in advance.

P.S. And Walls lv5 have neither mounting points for turrets nor reachable via wall ramps but the topic is not about it. Just saying. :(