I'm not sure if this is a mod issue or a game issue, but I'm putting it here because it started with a mod, I guess.

What happened was I installed the UFO follower overhaul, and after about 20 hours of playing with that active, I took a break from the Dawnguard quests and started the Civil War on the side of the Imperials. I played until I was to find the Winterhold camp, and I can't get anywhere near it without sudden CTD. I can circle it, but going near it, nope. I googled the issue, read forums, and took advice about CTDs. I verified my cache on Steam, it downloaded two files, issues continued. I downloaded Boss and TES5Edit, and where boss said I had ITM problems, I used TES5edit to clean them. Ran boss again, and now it says that I have multiple errors all saying my game will crash on startup because I have mods that require the dawnguard.esm and it's missing or inactive. That's odd because Boss found it the first time, and I've had Dawnguard since release, I was just playing its quests. I started the game just to be sure, and sure enough, instant CTD after the Beth logo. I went into Nexus Mod manager to see if somehow it had been deactivated, and it's not there at all. There's no Dawnguard.esm anymore. I went into data files via the launcher, and same thing. No Dawnguard.esm. I checked on Steam to see if it's still installed, and it is. I looked in the data folder, and there's the .esm just sitting there like always with all the others. I am completely lost here. After using Tes5edit to clean some mods, Dawnguard.esm is inexplicably absent from anywhere I could activate it, but Dawnguard is still installed and present in the data folder. Why would it suddenly not show up in nmm or the launcher?

I posted this on the Steam forums, and all I got was someone telling me to use Loot because Boss is outdated. I got Loot, and it's just telling me the same thing, that the .esm is missing or inactive, game will crash, etc. Hardly a fix, haha.

Okay, update: After deleting the .esm from my data folder, and having Steam redownload it, I was able to activate it from wyre bash and then it started showing up like it should. So now I can play the game, but I'm still getting the crash at the same spot. Guessing now the crash isn't a mod issue, and something else.