I actually don't think they did anywhere close to enough worldbuilding in DOS 2. They did a lot of "Immediate-Vicinity-building", but they left the WORLD as vague and undefined.
The Dwarves secretly plan to destroy Arx because the humans are a threat. The humans and lizards are at war apparently, according to a single note. Lucian decided to genocide the elves because he's a f***ing idiot, and the Black Ring, which was also genocided at the same time as the elves, still has a ton of forces all over the place. What you don't get is how all these pieces fit together.
