Tracks Help, my track mod doesn't load in AC

[ACFAN]

so i'm just starting off learning track modding and I have something very very basic at the moment. Just wanted to see if it was drivable.

I followed this tutorial

and exported to fbx using these settings

then I set up some basic shaders for the road, grass and kerb textures (nothing else is in the model yet) and exported to kn5

but when I launch ac in practice mode it crashes back to launcher.
I used the drift track folder structure to save time. file names match folder name and all are lower case.
what else could be wrong?
I just want to get something running first before spending time building a full model

here are the files if anyone needs them
https://1drv.ms/u/s!AgPMO1mLifl4wp04NBTV2tbnPhKKDQ

 

[Ghoults]

Check these:
https://assettocorsamods.net/threads/build-your-first-track-basic-guide.12/