Not sure how they are going to do things over in AKL, but when I did my GS in MEL, it was 6 weeks paid at your base salary.
Youll be fine tomorrow, just relax and be yourself. Make sure that you talk to people when you arrive and during the day. Everyone is in the same boat, so just enjoy it. Also, make sure that you are dressed suitably, ie - business attire.
Rusty