I'm sorry to say that I do not understand a word of it. Would anyone be so kind as to provide an example of how to lurp slurp... er, lerp and slerp?

For the reset-car function, you'd have to set a temporary vector (pan, tilt, and roll of car, I guess), find a variable for the car body (NewtonGetBody), and set NewtonBodySetTransform (body, temp vector). I don't know how to explain this, you ought to consult Agent_Smith's Car Tutorial II, it covers resetting after crashes. My system is based on his.