Excellent track! Modelling and texture work is top notch. The only thing I'm missing is the sensation of speed. The reason for this lies partially in the nature of the track itself (no trackside objects), partially in the somewhat monotone terrain texture. I have recolored the grass textures, changed the terrain multimap and adjusted the scale (0.03 instead of 1) of the multimap to have more variation in the terrain. Looks like a good temporary solution to me.
The killerfeature for this track would be (in my opinion) a huge multimap (or maybe 3 tiles, 4096x4096) based on an satellite image of the track. I believe SRW uses this technique quite often.
I wondered why there are no environment reflections (scn files looked ok to me) and it seems the value for the back clip plane is a bit to large (120km

). I have changed that to 80km (you can still see the mountains in the background, FogDensity=(0.00001) in SCN) and it worked. There is also an open bracket in the scn file (check static reflection mapper, Oregon_Raceway_Park_CW.scn).