Just wanted to make an announcement that this Rift (and Steam) game Unity source code is now available to learn from as Public Domain.
The game has passed the Technical, Content and Publishing reviews for the Oculus store and is released there and on Steam. Featuring - 55 levels - Race / Mission mode - Global Hi-scores / Replays - Level editor
Sadly the game didn't sell well, but I'm happy to help others. It took me 8 months to produce and release. Some gfx is bought and the music is done by another but the rest is done by one person.