If you go to the campaign folder in I think you're able to add them in the *.mis files.
There are several folders for the different years and different nations. forexample 41_taskforce_jp.
I'm not sure if you add more files here and add units to the files if they will be read and added to the campaign. I'll try this later and see what I find out - I'm not home right now...
Will post my results later
