The game crashed twice when I was playing the same Anu haven defense mission. Threat level extreme. The two times were during the Pandorans turn, when one of the Arthrons was firing.
Right after one random Arthron fired his machine gun arm, the game froze, even the music stopped playing. Then the music resumed and I thought that game would continue playing. But right after the music resumes, the games crashes and closes. I still could see one window with the Unity icon for some seconds, before it vanished. In both crashes the Arthrons were frenzied by a Scylla.
I couldn’t report this using the built in tool because the game closes after crashing.
EDIT: Loaded the save again today and got no crash so far.