For a few days now, actually I think over a year now in hindsight, I had a very bad gamebreaking bug, where upon loading a cell, the screen would go so dark it'd be unplayable even upon returning to the other cell, and that navigating outside of said cell would then be virtually impossible without console commands. I had a variety of theories, graphics card problems, memory problems- and it turns out it was those autoload doors.

(And by ruin, I don't mean permanently, but rather until said autoload door is replaced with a manual one).

I don't know a lot about autoload doors, they are kind of mysterious, and relatively new to TES games, if I remember right Skyrim was the first to bring them, so perhaps they are a relatively new form of in game technology for lack of better terms. This would also explain partially, why they are so complex, and bug prone I think. If I remember right, I also heard of some modders speaking of how they wanted to make custom autoload doors, but then I also read stuff, about how the way autoload doors function is hardcoded, and can't be altered with the creation kit, not 100% sure but like 99% sure that is what I once read. You can still do interesting things, like place autoload doors under holes in the ground, which essentially function very similar to those holes in some Zelda games that Link fell into, like there's a lot of potential autoload doors have, but sadly they themselves apparently can't be altered- from what I know anyways.

And apparently from my learned experience the past few days, autoload doors can also... I don't know, confuse the video game engine, or system or something along those lines, where the lightning can get messed up, if something having to do with autoload doors confuses it- or well that's my hypothesis. This seems to be a bug that is virtually unknown- at least I never heard of it, and I wish I could have seen someone talking about it ages ago, as it could have saved me so much time.

Please learn from all my experiences in this regard though, if you seem to be having graphical glitches or bugs, or graphical impairments, right around the exact same time you used an autoload door, a potential fix to this mod breaking problem, is to simply replace said autoload door with a manual door. Hopefully this can spare someone else of a lot of time, and frustration, I normally wouldn't make this post, but this seems to be a serious bug related to the Creation Kit that is almost entirely unknown.