Regarding this error, one thing I have recently learned about settings is that you can enforce certain values during settings stage, via something like:
data.raw["bool-setting"]["cb-enable-cold-warfare"].hidden = true
data.raw["bool-setting"]["cb-enable-cold-warfare"].forced_value = true
The hidden property is required for forced_value to take effect, and (as expected) hides the setting from the end user, preventing them from modifying it.
Not something I would recommend using very often, but when the alternative is an error on load (before the user can modify settings, in case they don't want to lose all of their other mod settings via reset), it might be the best option.
But yeah, if that setting is disabled (either by the user or some other mod setting its default value to false), then the error appears (I got a similar report here)
