Yes, I always have to ungroup when I give a command, then group again. It's very frustrating in multiplayer, and 50 percent of the battles I've lost have been because of the bug. Of the other 50 percent, 40 percent have been because I was too lazy to ungroup and stuff and thus chose a lazy solution to a tactical problem and ended up losing because of it. In short: the bug makes multiplayer almost impossible to use too, as if the siege bug that ruins singleplayer wouldn't be enough...