Also: Will exits that have animations for being locked use those animations to show they are frozen?
No, as they aren't "locked". Lemmings will even still become exiters upon encountering them, but they'll be frozen on the first frame of the Exiter animation instead of actually exiting. This way, eg. you can let it run, and see how many lemmings actually make it to the exit (by mousing over and seeing eg. "EXITER 13" in the help text).
