On CBR-MEL, you would be much better off actually booking the flights using red e-deals rather than award flights. The cost in $$$ won't be that much more, and you will earn points as well.
The taxes on this sector will include a fuel fine, and CBR and MEL airport charges, plus GST on all of them. You will pay these whether it is an award ticket or a paid ticket. I myself would not be wasting points on a CBR-MEL award.
Dave