3 Questions:

1) Is there anyway I can open a caravan deck like the keyring?

2) Is there any way to remove cards from the caravan deck?

3) Why has it let me have two of the same card in my caravan deck, and allow me to play?

- They are both Kings.
- They are both diamonds.
- They are both from The Tops Casino.

Screenshot of this -

http://i53.tinypic.com/34t1m60.jpg

I don't believe you can open a deck or remove cards from it. Only choose which ones you play.

As for the two kings, probably the game doesn't really treat the "base deck" that you get from Ringo as being from a particular casino. So you probably bought a King of Diamonds from the Tops and the game thinks that it is different from the one that is in the base deck.