Slitherine

Following options are turned on/off all at same time, no matter which single one you change:
Enable Bloom
Weather Effects
Permanent Wrecks
Autosave per turn (within scenario in objective screen)

Not sure if there are even more combined but that's already enough. In the end, either everything is on or off, although Weather Effects always seem to be on no matter what. You rather only notice it when you return to the option screen to check on your new settings.
I noticed it during scenario playing when suddenly the autosaves were done by the game although I prefer to do these manually. It's normally off for me but got switched on by turning on Permanent Wrecks or Weather Effects.
I have already removed my options.dat file, but that didn't help.

And lastly, I have also sometimes trouble using Exit to Desktop from the scenario-editor as long as the loading screen is open. You have to press Esc-key first to close that screen until the buttons become usable. Somehow, the dialog window lacks the proper focus to click on.

That's a heck of a spot, we'll investigate

It looks like these graphic options are always on. When I turn on Rain on a map, I can't turn it off via options. Same with bloom and wrecks which also seems always on.
At least the autosaves can be toggled on and off.