You probally did not have the AI 'turned on'. b4 you start the game make sure you go into the 'edit' function after you add an empire to the players section. select the two buttons (computer controlled, and Use race minister style). Make sure they are selected to be controlled by the computer and 'using style from race' for the use race minister style.
Should work fine after that. If you don't and are already in a game just go into the players menu(where the save/quit functions are) and de-select the races doing nothing, then manually turn on all their AI ministers and then re-select computer control for these races. (Good for scenario setup, let some races advance while others don't
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).
Hope this helps....
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"The Empress took your name away," said Chance.
Owen smiled coldly. "It wasn't hers to take. I'm a Deathstalker until I die. And we never forget a slight or an enemy." -Owen Deathstalker.