About the shotgun, at the campaing, you can use the riot shotgun, but in skirmish, there is a shotgun that fires different. There is no "ray" or "spray" of the flechettes, only a final hit. It´s very powerfull.
With the alien base, is sufficient pass over them, or is necessary patrol the area for a while?.
Another question? is available an alien ECM in the 2.3.1? i can´t use the alien astrogation or the alien detection, but if i´m not wrong, it was possible on older versions.
Thanks again.