I used http://geckoblue.livejournal.com/284897.html to get my OUYA controller working with AC2. I then thought it might be interesting to try with the original game.
I dug around and found the key mappings at
C:\Program Files (x86)\Steam\steamapps\common\Assassins Creed\DefaultBindings.map
Then added the exact same code as for AC2. The game played like I was drunk, spinning and impossible to control. I eventually managed to get in to the options and hit the “Defaults” button for the OUYA which appeared to load my mappings and the game worked fine after that. Hitting defaults was somewhat of a struggle without the ability to move down.