Didn't have that issue myself but my guys are getting killed left and right once they run out of the skyranger. Not an issue with smoke grenades. And hey, its occupational hazard.
I do have a problem with the AI when I go up a very large ufo, it seems if they're surrounded by 2-3 humans they don't know what to do, and I don't think it was because they panicked and dropped their weapon.