Just ran the demo and....wow that track is really amazing, did you make that yourself?!
I got a smooth looking 31 FPS, kinda reminded me of PS1.
The car model, get rid of it quick!! Its too high poly and doesn't fit in with the gorgeous track, even for a demo! All that yellow...yuck! Who wants a Merc anyway - stick in a Ferarri asap
I'm not here to talk about the car model tho, but then again I'm not sure what to say about the physics....
The car vehicle itself actually behaved quite well, bouncing on the suspension nicely, collision detection, running over the curbs. Really rather good. Better than I was expecting in fact!
It was just the turning...
Obviously you were missing the tyre slip commands, which I understand are in the update patch out today? (like, a week after launch?!) Unfortunately, for this demo, this meant that the car handling was rather unrealistic when turning, it was as if you had super glue on the tyres. A few times the car would swing right round in a corner, leaving the camera kinda looking face down at the seats.
Other than that, yeah, the camera needs work, especially when reversing.
Also, the collisions with the walls were not so hot - you just "get stuck" rather than "scrape" down them (with sparks, eventually?)
Also I was amazed when I ran over a cone (expecting to see it go flying off, realistically)....the car just stopped dead and twitched about
Having said all af this, and knowing that DP is so young, I have to say that this is one of the better amature vehicle physics demos I've ever played!! Period. At least the car was generally controllable and had some semblance of speed (I'd like more tho!)
I'd really like to see another demo with an updated camera and the trye slip commands all in there.
All in all though, I think this demo bodes well for your game and for Dark Physics in general