Adelia's two levels are both on the single map, you can check the shbd file, the client is just hard-coded to use a different mini-map which splits into two sections (depending on level), likewise with the ride which is also hard-coded into the client to warp you up/down.
A warp gate on both levels would be suffice (unless otherwise tested), your only loss is in the mini-map, which is better than not having Adelia at all.
I remember there was one .exe a friend fixed for Dusk which was able to load Adelia without running out of memory, not sure if it ended up working suffice, but finding that .exe would be a start if the lower level fails to function. (as its a height map)
Our files are already out, you're just going to have to do some more work than re-configuring some .txt files to get them working.
