/vr/ - Retro Games

So here's what I'm going for and how I'm trying to do it.
Player crosses a line and from there the room fills up with water (swimmable).
Pic related.

Normally I dont think it would be that hard to pull off, but the thing is the water is going over several 3D floors, some of which go over other 3D floors.
After this time the player can then swim around the entire room.

On a technical basis, this is how I've tried (and failed so far) to do it:
>1: Player crosses this line (has the "ceiling raise to nearest flag").
>2:The sector that is currently controlling the water (swimmable) then "raises to nearest" sector.
>3:This sector has the water in the room rise up to this line.

An anon last thread was kind enough to show an example which I've been going over, however in his example the rising liquid cannot be swum around in.