I got soft lock during an alien turn, had breached the ufo with C4 a couple turns prior and one of the aliens ran out of the ufo and stopped, the turn then would not finish. If I get it to happen again I'll record a video with shadowplay or something. I'd guess it'd be some pathing or AI error where the alien couldnt decide on who to shoot after it left the ufo.
I also noticed maybe a bug but I couldn't select smoke grenades from the grenade belt when there were frags still left, same with flashbangs. I might be just missing how it works or something but I tried left clicking (which just draws it), right clicking (does nothing), middle mouse clicking etc.
Another issue I noticed, left clicking the grenade quick access will trigger alien overwatch, not sure if this is intended or not. One thing that mustn't be intended is that this overwatch, if it hits or not, stops you from actually using the grenade