I couldn't get the 3D to work - but I have to say, I love the way the world 'zooms up' around the player as they move around. Adds a lot of drama to what would have been a fairly static scene. Well done.
Thanks.
It looks like the 3D button only appears after a click on the "Change quality" button. When active, the "3D" button is converted to a "+3D" with various settings for the 3D display.