Can I just set it up in the module properties (if so where, I don’t see an option like that) or does it require more work then that?
It require a lot more than that.
Some poeple have made stuff about it. But a lot about character progression is hard coded (a lot related to melee is hard coded, BAB and things like that where nothing has bezn done about it).
The best is to stay at lvl 30. 30 to 40 won’t be “real level” unless you can alter the main “NWN2.exe”.
I don’t see the interest of that lvl 40 I know it was the lvl for NWN, but what trully matter is the “power curve” character vs “world”. The lvl max is irrelevant in fact. It’s just that " the scale" needs to be made for 30 lvl. But 10/20/30 or 40 doesn’t change anything in the end. It’s always the progression that matters, the “power curve” Player vs world needs to make sense, the “number” doesn’t matter in the end.
lvl 30 is “god like”, 1 is “beginner”. And you juste have to scale the world around it.
I agree with most things you are saying however there are certain builds which can’t reach their full potential within 30 levels cap. Like self concealment feats that can go up to 50% but within 30 levels at your disposal you will never go beyond 30% and limiting yourself in other aspects at that.
Download the level 160 cap mod and then limit it to level 40 via the Campaign editor plugin of the toolset.
Up to level 40, all the hardcoded stuff works properly with no necessary workarounds. You can even delete the override files of the mod if you want to have an experience that is more similar to the original (for example with prestige classes capped to 10, in level 160 mod with the override files they are capped to 40 like base classes).
From level 41 on, most of the stuff works, but the override files become necessary, and even with them you will still experience some bugs/issues especially with casters (there is a detailed readme on the mod page about that as well)