In the opening mission ( I was replaying it recently) for the Altarian campaign, the population of all your planets will decrease to values of 0, no matter what you do to increase the pop. This makes it impossible to load any transports, among other obvious issues. It does not result in a game over, but it does make beating the mission impossible. This only occurred after upgrading to Crusade. I am not certain how many other campaign mission are affected yet.
