mono is not an editor. is an open source re-make of the .net libraries.

What they need was not another language they needed a solid manual/library reference like the one gamestudio has. I have torque3d never really used it except from playing with editor. It's not because my lack of skill, i used a wide variety of engines, even written a not-so-mine engine(ogre+openal, not for games only for a 3d presentation), it's because lack of "good" documentation.