Op, for what its worth, a few years ago I was flying from LAX to AKL with Air NZ. I was BMI Silver at the time and the trip from London to LA, and then LA to AKL with Air NZ would have made me Gold....I rang up the Air NZ call center to book the flight (LAX-AKL) specifically asking if I would get miles, agent confirmed and I ended up only getting half the miles.

I wrote a letter and go a reply saying nope only half miles.