Jeff, first off, thanks for the LR4 tutorial videos. I thought I knew LR, but didn't realize how little I really knew until I started watching your tutorial. Very well done.
Let me repay the favor with some advice on NZ. By all means find a competent guide, don't do it on your own. Jackie Ranken in Queenstown is one, but there are others. They know the best spots, the best times and can suggest alternatives when the weather turns foul. By all means hire a helicopter (doors off!), but do not opt for the packaged helitours, they stuff too many passengers in to make shooting feasible. Same suggestion for an airplane (single engine, 2/4 seat, doors off). Flights will be expensive, but worth it. I just did this in Namibia and got some spectacular images of the Skeleton Coast. You must do Queenstown and Milford Sound, I suggest an overnight cruise. Doubtful Sound wasn't all that interesting to me. I didn't hike the glaciers due to weather, but saw them by air. I could fill a book on this topic, so if you have questions, let me know.