I have not seen any script or other way of saving an AI or Custom Plays to your Hard Drive. There have been multiple suggestions in the Suggestion Forum to allow users to save an AI and custom play to their profile and other. I would suggest going here:
http://goallineblitz.com/game/forum_thread.pl?thread_id=2502381
In the meantime, just find teams that will allow you to transfer your AI, just to save it.
http://goallineblitz.com/game/forum_thread.pl?thread_id=2502381
In the meantime, just find teams that will allow you to transfer your AI, just to save it.