thats what i'd like to see ,too although it might be a little dificult to remove the sci-fi elements from the campaign as they are a main part of th story.so a whole new campaign would be the solution. maybe we will see one some day.
you can change wether you are allowed toe save in turn based or realtime with the editor open the dificullty you like to change and you will find something "saving allowed" and behind that may be realtime or always thats it always able to save on impossible.
have you done the data source thingy described in this thread: http://s2hq.com/forum/viewtopic.php?t=62? after that you will have to connect to the server . i figured it out really fast. cant explain it more detailed right now becaus i ain't at my own machine right now. hope it helps you a little bit. otherwise i will try to explain it better once i return to my pc.