As far as the terrain editor goes, a lot of the tutorials created for the first game are pretty relevant. Once you get past project creation and you're at the point of creating a terrain, you can make use of these:
The Divinity Engine Toolkit Tutorial Video Series My main priority this weekend (besides helping answer questions) is to get my demo mod uploaded to workshop. After that, I will try to spend more time writing community guides. I was waiting a bit until Larian published all that they have because I did not want to duplicate efforts, but I'll try to get more content out there soon.
