Entry fee will be $20 like usual I'd say, and practice 9 - 12 and racing at 1. You'll get 2 race runs and to do the race you have to complete at least one practice run.
Gotta have MTBA membership ($15 for the day, {Junior} $60 for the year {Adult} $80 for the year)
Not sure if you require a membership in a MTBA affiliated club anymore, but I'm guessing you do. Its $20 bucks to join the Cairns club for a year.
And remember your fullface.
Disclaimer: That information may not be 100% Correct, haven't spoke to Gordon, but it will give you a VERY close idea