UPDATE : I don't know what you did, but now it's not cpu-intensive anymore and works perfectly.
It feels like you optimized it. :)
A great track for little cars, karts and stuff.
(I'm not into drift and I feel that it's too short for powerful cars)
Nice scenery and impressive HD textures.
Also, it reminds me of good old times in rFactor. :)
Some trees look a bit out of place and it would be nice if they "merged" naturally in the landscape.
A great Japanese track!