I have actually done a lot of work on this. I have been boiling down the main campaign story and now have a version of it that will build on a fresh game, currently its relatively untested though I did as little as possible to change to change the workings of it. So as far as I am aware it works nearly the same as the main campaign (mostly I changed the number of player requirements to support N players). If you would like to help test what I have and possibly improve/bug fix it, send me a PM so we can figure out a way I can transfer what I have to you.
Here is the almost up to date info of what I have discovered in the main game and should function in my version of the scripts: http://www.larian.com/forums/ubbthreads.php?ubb=showflat&Number=556205#Post556476