From memory 70% pass mark for the air law. There is a separate Instrument Air law exam (whatever you do - DON'T call it 'IREX'). NEITHER are open book - study required. Some have waltzed in expecting it to be a breeze and failed. Usually if you prepare you will be alright. The laws are based on the NZ regs. Pay particular attention to things that are different from Aussie regs if that is what you are used to.
For the instrument exam they will provide a copy of a couple of approach plates for interpretation. If you are doing ATPL air law you will need to know part 135/125/and 121 rules but if you do CPL air law you will only need to cover part 135 (think of it as part 135 - smallish aircraft VFR only, 125 - medium/IFR, 121 - transport/airline). They are not the only areas to be studied though obviously.
Keep trying CASR website and download the lot if you can. One of the PDF's will give you an outline of areas covered in the exam/s. Goodluck!
