Why won't my drawing tablet work on my Macbook Air?

ANGER!
I just plugged my Wacom Cintiq 20WSX into my Air. I have the most up-to-date driver for it, I have the Mini-DVI cable plugged into it. I know the tablet works, I know my Mini-DVI works, however the tablet shows nothing on screen.
WTH? Why doesn’t it work? Does anyone know of a keyboard shortcut in Mac to gather all the windows on a single screen? I think the monitor is out of a range and that is why it is not working.