I started a new car racer loosely based on that old one I wrote a few years ago, with the intention of fixing mistakes of the past (I had, for one thing, because of the 3ds format's incompatible orientation made that game in the X/Y plane, instead of the X/Z). This time I used OBJs. What's odd is that the world is upside down: rotating around the world's +Y axis turns the car right, but translation on +Y goes up (and the SkyBox is upside down). The models are properly oriented on Max, so I really don't know what gives.