Hi Carl,
I haven't been to DMK before, but have raced a laser scanned version on rFactor2. I must say, this is an impressive start. Real talk, I felt your previous one to be a bit lacklustre, very sparse, and quite basic.
This one is far more impressive, and I commend the progress you've made. The difference between the two is unrivalled. Blender can also be a bit**, so fair play to you for sticking at it.
I've found some barriers are not collisionable so when I inevitably spin off, I find myself in the abyss. Aside from this, excellent stuff. Look forward to more updates.