Hello, 

I'm not actually sure whether this is a bug or intended, but the "Unwanted Oxidation"/"From Dust to Rust" event/quest will trigger even when the "Global events" are disabled in the pre-game options. So either I'm missing something, either it can't be disabled (but why ?  It's extremely frustrating against AI since they never participate so you have to do everything alone, there's nothing "competitive" about that), either it's simply a good ol' bug. Maybe because there's an associated quest ?

Especially since it seems to happen literally every game, and pretty early at that (just happened on turn 47 on Fast, that's insanely early).

Side question : is there a workaround by meddling with some files maybe ?

Ok so if anyone else cares, here's what I've found : this quest/event is defined in the QuestDefinitions[GlobalCooperative].xml file found in the [install directory]/Public/Quests directory. (It's the quest number 004) It's definitely classified as a "quest" and not as an event (i.e. the things like +4 influence on anomaly or -2 dust aren't there - and those are the ones disabled by the option). So I simply deleted the whole block with this quest (leaving the others) and it seems to work. I reloaded a save I had right before it happens (which is not hard, as it happens 80% of the time, and almost always between turns 45 and 50) and it didn't appear. Maybe the effect still got added without a way to remove it but I don't think so.

So yeah, deleting the quest definition seems to work so far. Any patch will probably change it back but it's easy enough to do again. Of course, I'd prefer if I did not have to meddle with files to get rid of this (terrible) event but at least it works.