I was curious to see if any of the F4SE plugins reported an issue before calling Exit() or something to that nature. I've noticed an up-tick on just exiting to the desktop without any 'fatalities' being logged(either by Buffout or Windows itself via a application exception). This almost makes me think it's in the NG version of the Fallout.exe. Though with a modded Fallout 3 I had one just as I was loading into the game after using FWE to select a 'vault' dweller- I didn't notice that in the other attempts and have upgraded to Windows 11 since then(maybe something in the way the OS is handling something? not sure).
Since that's the Capital Wasteland, which should be a ground up recreation of Fallout 3 assets it doesn't seem to point(at least initially) from some type of weird 'drm' at a plugin level to keep plugins from being loaded into a CK- or something else like a way to 'extend' something else outside of the normal game's logic. I would guess it's a missing form(an item in the game as each thing that's defined pretty much has a formid associated with it) or something that's mis-configured or set in the plugins packets(IFF records in the plugin itself).
Does this equal the number of settlements where nothing is built? or just 'owned' settlements without a power grid like you were thinking.
This soulds like a user defined keybinding file- where the MCM stores it's custom keyboard shortcuts- maybe.
That makes two of us.

lol