Alright, I dug into that a bit.
Right now, I was looking at the tutorials and created a config named "custom_story_settings" in the story folder for my custom story, with all the info for the story and crap. And that works.
The thing is though I added a line
<ConfigFiles
Game = "custom_stories/MyStory/Configs/game.cfg"
/>
and went into my game.cfg (I copied the original and put it in that folder) and changed the sanitylosspersecond line
<Player_Darkness
// buncha codes
SanityLossPerSecond = "0"
// buncha codes
>
However I don't think it worked, because I left my computer afk and came back and my sanity was dangerously low (tested it by letting my guy sit in the dark)
Also it doesn't seem to disable your screen slowly moving in and out (which is kinda annoying) so is it possible to disable that one?