So, I just watched it. I had to register at rockworld.tv and pay 1£ (one british pound) to watch it. It's availible now any time you like. It was pretty good. I learnt a couple of new things about the history of black metal.
Anyway, if you wanted to see it just because of frosthardr, you might as well just watch the trailer. They weren't given a lot of time, probably like 30 seconds of this 64 min documentary. But they still had a big part. They were the only christian metal band mentioned. Most of the talk about christian black metal bands, was done by non-christians saying it's quite a contradiction, and that it doesn't work. They claimed that there can be christian metal bands, but not christian BLACK metal bands.