Oh, I forgot to mention two big crashes, which I am pretty sure were intentionally programmed, but actually caused unreal engine fatal crashes. A force-close is one thing, but an actual "Fatal error" is kind of overdoing it, unless the message itself is just faked, in which case you should seriously consider changing the error message to make it clear that the crash was "intentional", or at the very least, not related to actual hardware/software issues.
Also, if events can cause crashes, it absolutely NEEDs an update to the auto-save system to actually auto-save prior to any such event, even if it's a hidden autosave that doesn't announce itself, to maintain the surprise. It's too realistically possible to be on your ATV all day and miss all the autosaves leading up to an event that crashes the game (again, assuming they were intentional, I've listed the 2 I ran into below).
I got some ominous music one night and lost the ability to pause (this was before I realized this meant an event was in progress). As the music wound down, I wandered over to sort some of my tables, and the game froze and these bars of rainbow nonsense, similar to some sort of rendering error, grew on the screen in a thatched pattern, leading up to the crash. I was able to screenshot the artifacts, meaning they were in the render buffer, and not a physical issue, which is why I think it may have somehow been intentional.
The second time I got the same pattern, I got some tool-tips indicating I should check out something going on in the mountains. Not sure if it was the picknickers or something else, I checked over the mountains near the strange box with the tile-lock. As I approached the mountain, a black particle fell into the mountain, which I assumed was just a firefly sprite disappearing. When I went over the mountain, the black particle was now a flat featureless square sprite pulsing as it moved down the mountainside. I approached it, and accidentally rolled into it on the ATV, and the game froze and the rainbow artifacts grew out again.
