I am not guessing the LoG editor to have the complexities of source or the classic worldcraft, unreal editor... etc... I see the mapping part of the editor more as a 2d editor, carving with cubes or squares...
Other question is the lightning and of course the script system.
but it will depend of an important question...
Is LoG a Classic 3D game tweaked to fit the squared universe? or is it designed from scratch as a step by step travel system ?
I mean, Could be LoG a classic Doom respecting to the nature of the engine?
Truth is out there...
Greetings.