what they did is based their dev tools on unity. you load the part tools into a project, set it up, and it exports your parts. it has its pros and cons. since it only outputs models and textures, which is what you put into it, so its kind of redundant if you ask me. on the other hand it does automate a lot of the crap that comes with editing parts. once you have set up the scene you can save it and re-load it if you ever have to change something. it also has a pretty good cockpit editor, you can place props and see what they will look like in game. you can also place effects, which i haven't had a need for yet. you still have to hand edit cfgs, and compile plugins to dll with visual studio (or mono dev). so its not a complete package.