This might be the worst trash I've ever seen in AC modding history.
For whatever reason, the author decided to put the ENTIRE CAR MODEL under 'CINTURE_OFF' dummy, which means once you enter the track, car will be invisible because everything inside 'CINTURE_OFF' will be hidden once on the road.
I had to extract the model, put it into blender and rename the chassis dummy, it's just unbelievable.