Well, I kinda designed the backpack thingy to be used while the creature is both on verticle and horizontal land. While horizontal, the two doors give passanger access to two seperate compartments. Supplies can also be stored inside, and on the rack on top (or on the side, depending on which way up the lizard currently is) of the pack.
Then, when the lizard begins ascending or decending, the pack/box is tipped on its side. Passangers will be able to stand on the divide between the two compartments and look out of the windows. The supplies are all strapped safely against the side so they don\'t fall off.
[Edit: And I gave absolutely no thought as to how the creature could be controlled, so don\'t ask.

Actually I was going to draw a little man sitting on top holding a pair of reins (sp?), but this wouldn\'t have gone well with my two-sided pack idea...]
[Mind control, anyone?

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