After every attack, any dwellers that area attack go into idle mode and leave their posts. This is very annoying once you get over 100 pop.

You should try it with a near 200 cap limit. Either the characters are in the wrong rooms or are idle or are dead... I think they rushed the patch out to match up with the Android launch. The Deathclaws sure as hell don't behave right. They run away from enemies without guns for example. It seems they have X number of seconds per room and then they have to move.