Question to the riders familiar with Tianma Circuit : how can you ride on the track (not to race, just to have some track time) ? Do you need to book in advance, or just come to the circuit whenever you want, pay a fee and ride ?

I guess some riders here do it sometimes, how is the track and the usual track time : many bikes and cars allowed at the same time, what about driving/riding etiquette (people cutting you off or basically ok) ?
Just to know what to expect...