You reinstalled Windows? That's commitment. So you've essentially replaced everything but it still doesn't work... This might be above my area of expertise but here's what I think: Your log looks fine actually, none of those warnings seem to be of critical nature. I still suspect that it might have something to do with the savefiles...
Try this: Delete/move the saves folder of the game AND open your Windows search, type %appdata%, find the RenPy folder, then delete/move the Eternum-[Numbers] folder. Or heck, try deleting/moving the entire RenPy folder if you need to.
Renpy keeps a second set of saves in the user folder, maybe those cause trouble. If that's not it, I'm out of ideas. Maybe a driver problem of some sort, idk. EDIT: Make sure to tell me if it worked, I'm curious :P