I agree with turning off the damage, and don't think having the track broken into sections helps. I think the sims that have it broken into sections are just so people can have shorter races on certain areas, but not necessarily for learning the track. There's definitely a flow to it, and it helps to run it straight through. I learned it years ago. At first, I kept starting over when I messed up (similar to running individual sections). But then I turned damage off and kept going and end up learning in very quickly after that.
The problem with starting over, was that I wasn't getting a chance to see the rest of the track, not every area of the Nords is as difficult as others. By starting over, you're limiting yourself, and not allow yourself to learn the other areas that you could pick up on easily. So when you finally make it past that one point that was giving you problems, you then only get a little further down the road and crash again. Not because the next area is hard, but because you've never seen it before and it's unfamiliar. Every complete lap you run, you learn a little bit more about the track.
The key to learning the Nords is to drive it like you would in real life. In RL, you wouldn't go any faster than you were certain about what's ahead. Basically, unless you know what's ahead and/or are sure about how to take the approaching corner, you shouldn't be hard on the throttle. Also, in the beginning, don't worry about your lines. You can't find the right line, until you know the corner, because the right line is dependent on your entry speed and braking points, both of which require you to know the corner you're heading into. When first starting out, just drive the track, don't race it. Pay attention to the scenery. It will help you start learning where you are and what's next.
Do you break other track into sections to learn them? No. You start slow and build speed as you learn the track. The Nords is no different. It's just longer. Start with slow laps and build speed as you learn the track. And just like any other track, you'll see your lap times start to decrease. And you'll also feel less frustrated. To me, nothing would be more frustrating and monotonous than running the same few miles over and over, just because I'm blowing one turn. If you approach it that way, it'll be a month before you ever start enjoying the track.
