I'm having a heck of a time right now, I've been toying with the LOG2 editor (awesome that they shipped the game with it!)
For the life of me though, I can't seem to make an outdoor area. I put forest walls and such in, and I get total darkness. I can't find where to place light, or to change to an outdoor construction set.
I guess I should check wiki, yeah, but is it updated for working with the Grimrock 2 dungeon maker?