It's a good effort, but its not very accurate at all.
I was at the laughlin Pro-Am and have seen the track in person.
I'll help you out a bit with what i can see wrong.
1. The first straight does not angle outwards. From the start its a 90 degree turn to the first straight.
2. Your sweeper pinches at the end, while in-fact it does pinch a bit, yours is a little too exagerated.
3. The chicane you have is too shallow. From where I was standing in the pits looking at the chicane straight on, the clips were all in direct line with eachother. Possibly overlapping a bit. your also missing a part of the judged section. Where the course ends, the cars are driving towards the starting grid, then make a sharp 90 degree turn back to the pits.
Try watching more clips of the pro-am. There are numerous clips from in-car cams around youtube.
Hope that helps. I'd really like to play this course once it's complete.