Larian Studios Forums Divinity - Original Sin Divinity Original Sin - Mods MainCampaign -Canｴt generate AIGrid /Terrain/ Save

Generating AIGrids in my own Modules works well - but I can`t seem to get this to work in the MAIN Module.
All Buttons in the "AIGridPanel" (Full Generate, Partial Gernerate, Seed Fill...) are greyed out.
I place an AiSeeder and they stay greyed out.


I also can't change / add Terrain.


When I try to save I get the Message:
You need Developer Rights to open the the file: .../Levels/Cyseal/Items/items-...? Opening Steamas an Admin doesn`t help.


I can add and delete Objects and change their Attributes though...


What am I doing wrong? Are we not supposed to play around with the MAIN-Modules Levels? Or is this just because of some general mistake that just does not occure in my own Modules?