The majority of this mission is in pitch black. It's not that the author did a bad job of lighting, its that they intentionally hid things in the total blackness.

Blackness isn't ambiance, it's a way to tell your potential fans to take a hike, you don't really want them to play your mission. Required gold and access to the main quest item you are meant to steal are fully submerged in total blackness.

Just to thoroughly show you that the blackness is something the author insists upon, there are light sources added to the mission that aren't attached to an actual item. (no torch or lantern, etc). That light serves only to make sure you can't sneak up on the guard. But everything else... total blackness.

I guess the name of the mission is a joke too, "Dark" walker... but it wasn't named correctly as once you load the mission it says you are playing "Thieve's Guild".

The author did make some impressive stair cases and blah, blah, blah, if you wanted me to say something nice about your mission, allow me to see it! :p