Cube 2 missed an opportunity, I think. I loved that octree-based map engine. Here was an accessible and powerful cube based engine from before Minecraft was a twinkle in Notch's eye. To this day, I don't know of any other engine that lets you collaborate with multiple people in real time as though it were part of the game - and with level editing so easy, it could have fostered the kind of mapping community not seen since the days of Doom, Quake, and Unreal (1/UT/2004).
Now everything is "model it in 3DSMax, Maya, or Blender." Complicated tools, meandering workflows, just a time consuming process in general. Even Unreal is like that now. Why use the shape editor when you can just import your model? Does the new engine even have that tool anymore? No it doesn't. Just import or use an existing mesh for your complex details. Want to make your own but don't know how? Time to learn this other tool over here.
I'm not complaining exactly. I'm pretty good with Max and Blender. I'm just reflecting (as an amateur) on what mapping felt like in the past, and how it compares to today. It was pretty straight forward back then. There was probably a lot of pent up creativity from people who didn't have the time to learn multiple tools. Minecraft quenched their thirst, but the Cube 2 engine could have been the thing to do that. If only it were better documented, and positioned better as an engine for hobbyists.
The farthest I got with it was map editing and compiling it from the source. So I know what you mean. It's been a while, but I doubt anything has changed. Sorry to hear about the state of your game.