@SpunkyB21 Menyoo and simple Native Trainer essentially do the same thing, yes. If you open SNT and go into model spawning, you should see the protagonists as the first three entries to spawn as. Just select one using the numbpad keys and use num 5 (going by the default keys) to select it and you should spawn as that character.

I don't use Menyoo, I run SNT, but isn't there an option to spawn as one of the protagonists? if not, temporarily use SNT to change back and then make a new save.

Try disabling your mods folder and load into the vanilla game to see if it loads. The issue I had was more related to the gameconfig

Might be a good idea to ask this on the LCPDFR site for the mod (or per the author's directions) too as @Yogeshk mentioned. It might help with faster/better feedback from the developer or those using it.

You can only save as one of the protagonists. Swapping to anything else won't let you so that it won't break the game all to hell.

That's odd. Running the latest version (assuming no new DLCs were released today) and WOV and other mods work just fine. You probably should check with the devs behind the mods you're using and their associated mod pages to check on updates and bugs, etc. Also, openallinteriors works just fine as is. There is another mod called Online Interiors that builds upon it

I only read the title and I was thinking "How is that a problem? I have something to unwind with while messing around in games on the weekends." and then I read the actual thread.
You might want to try waiting for the model/ped to sober up and then make a new save with it and try loading the new save to see if that helps.

You are clicking the Edit Mode button as well when you're adding stuff into your mods folder using OpenIV right?

None that I've seen that covers the entire game/map. I know in FiveM it works, but that's because of LUA scripting (I believe) done by those that run particular servers .

FiveM is a mod for GTAV that does not work on any SP assets or mode. It's essentially a non R* GTAOnline mode