Ditto, I want to use a custom resolution, so I need to locate the config file, which is not in a standard spot.
I have triple monitors, and this game has poor support for this feature (Nvidia Surround / Eyefinity). The interface should conform to only the primary monitor, but that's pretty rare since the feature has never really caught on (but it's still officially supported and some games, like Far Cry 5 have excellent support for it).
The way to get around the interface / cut scene stretching in games like this is to just run the game in a custom resolution that only utilizes some of the 2 extra monitors on either side. I have 5760x1080 of real estate, and I'd like to run the game at roughly 2800x1080, which should get rid of all the stretching problems.
I can run the game at the full 5760x1080, or the random 3840x1024 it gives the option for, or 1920x180, so I know this will be physically possible to do once I get into the config file.