Thanks for reporting on your experience!
A strategy that occurred to me today is to simulate a dead loved one. This would be difficult for a human to do but shouldn't be hard for a sufficiently intelligent AI. If I had a dead wife or something I think I would be incredibly vulnerable to this.
For a religious gatekeeper, you could simulate a prophet sent by God. As a superhuman intelligence, you might be able to find out what exactly they consider the will of God, and present yourself as an avatar sent to do exactly this. However, humans have a free choice -- the gatekeeper is allowed to become a new Judas by not releasing you. Or rather a new Adam; able to drag the whole humanity and future generations into the darkness of their sin. This conversation is God testing the gatekeeper's faith, and judging the whole humanity.
For a rationalist, you c...
Update 2013-09-05.
I have since played two more AI box experiments after this one, winning both.
Update 2013-12-30:
I have lost two more AI box experiments, and won two more. Current Record is 3 Wins, 3 Losses.