I don't own a Mac but may I ask, does the game ask you to purchase or enter a purchase ID when starting up? If so, check your email. You should have recieved a code that needs to be entered into the game to remove the Trial features.
The Lahman database is needed in order to run historical leagues. You can get it here:
http://www.allsimbaseball.com/index....d=26&Itemid=67