Those are the Betty bombers with the Ohka kamikazi Divine Wind warriors... I have not had any CTD with those previously, but then again, I have not had a mission that had more than 2 previously... I'll look to see how much they "steal" of clock cycles... I don't understand (again) why you are not getting survivors to spawn... but a "symptom" might be the fact that they are set to enter AFTER the war... I'll try running that mission again here. They have to be set to enter AFTER the mission start for the "spawn" trigger to work, but they probably can't be after the end of the war, which is actually in August... I'll try to get to looking at that tomorrow afternoon...
PS: The night attacks did happen with the Betty laden Okha, just not as often. The problem with them as an RGG is the timing... once they spawn, they go until they die... I might move the group's spawn location in some, and that way you get the earlier, and they will quit spawning sooner... AND - apparently I have to reduce the amount of them that spawn?? lol