Hi guys,

in 9h of game time I've just had the game crash on me for the second time, and not in a good way. By which I mean that it doesn't simply crash to the desktop, but it locks up the entire PC - keyboard stops reacting, no way to Ctrl-Alt-Delete, everything is locked up and I have to do a hard reset of the computer to recover.

I think this might be related to audio - I'm playing using my headphones and I accidentally disconnected them while playing. I think the same thing might have happened the first time.
When I disconnect the headphones, my system automatically switches to the speakers, could be this switch of audio device is causing this issue.

Let me know if I can provide some kind of log.

The logs have since been overwritten. But if it happens again, I will check and send them.
I'm now taking alot of care not to unplug my headset while playing though...

That really sounds like overheating to me.

Without vsync on the game will attempt to generate an insane amount of frames per second.

I would add command to "Set Launch Options" or to the end of whatever shortcut you are using.

-targetFPS60

This caps the framerate at 60 regardless of vsync.

To the developer (d_martynenko) you really should cap the framerate to something and not let unity just allow it to be an insane number. In my testing I saw it spike to almost 300 FPS - that is a huge load on GPU/CPU for no reason.

StartupSetup.Start - > just add close to the top to "Application.set_targetFrameRate(60)" would be my recommendation.

No, I don't think it's overheating. You might not have noticed, but there is a VSync option in-game: Settings -> Game -> Vertical sync, and I have it turned on.
Also checking MSI Afterburner and simply listening to my ventilator, the gfx card is not even trying hard when running the game.
I'm pretty sure it's a weird audio issue related to switching between audio outputs. My system had a sound card, which is a rarity these days (SB Audity), in addition to gaming headset, monitor speakers, attached VR headset... if I have every sound option enabled, I can choose between 8 or so different outputs, however I have most of them disabled so I only see the most important ones when switching output devices.
So I'm afraid my problem is probably specific to my system configuration and hard to test and reproduce.