It really depends on what you're looking at. For terrain placement and such, NWN2 would be completely different. The included documentation (in the folder of the same name) goes through the basics well enough for that. The rest is more about experimentation.
For scripting and dialogue, it's essentially the same, with some small additions. You can go through some NWN1 tutorials for scripting, and that'll benefit you a lot for NWN2.
As for a hakpak, I'm not sure. NWN1 had an included tool to create such a file, as well as a hak folder in which to put them in. I see neither right now.