X² freezes on Linux (Steam version)

[HashtagMC]

Up until today, X² ran quite well on my Linux laptop. I'm running Mint 22.1 Cinnamon, and using Proton 6.3-8, X² ran perfectly fine. The occasional crash, but not more than on Windows.

Today, my Nvidia driver updated. First, it screwed up my Steam as a whole (wouldn't even start), and after a couple reboots, while Steam would run, X² would not. At first, it wouldn't start; then when it would, it would freeze after a couple minutes, more often than not taking my entire laptop with it.

So naturally, I rolled the driver back to an older version. Since I wasn't sure what the old version was, I downgraded from 570 to 550 (which my Driver Manager told me was the "recommended" version).

Well. It still crashes.

Before today, X² had been running without issues for months, so I'm really quite puzzled. If anyone has any advice – any places where I might find logfiles that tell me more about what happened, any Nvidia driver versions known to work with X², etc. – I would be grateful.

Specs.

Thinkpad T550
CPU: i7-5600U
GPU: Nvidia GM108M (GeForce 940M)
GPU2: Intel HD 5500
RAM: 16 GB
OS: Mint 22.1 Cinnamon
Driver: Nvidia 550
Steam version: 1757452101
Game version: 1.5 with Bonus Pack (Steam version)

Edit: this time, it crashed less than a minute in, and the sound was also looping every few seconds.

Edit 2: Updating to 570 again didn't change a thing. Furthermore, according to the update history, 570 was running before the update as well, so idk what Nvidia stuff got updated, but it wasn't an entire driver version. Other games work, so this seems to be unique to X².

Edit 3: 580 doesn't either, and nouveau not only doesn't recognise my GeForce (ask me how I know), but Steam doesn't even start with it.

Edit 4: Purging all things Nvidia and installing it fresh doesn't help. The game doesn't even get past the first splash screen. Enabling "alternative video playback" fixes that, but the game still freezes.

Edit 5: Some interesting discoveries. I ran the .exe directly via WINE instead of going through Steam. This way, the game only detects the on-board Intel graphics, which is perfectly sufficient for it. However, it still freezes.

[HashtagMC]

Okay, looks like I might have to eat my own words here: the issue only happens in my current save game, which is modified. I've been working on a script the last weeks, and while I don't see how it's the cause*, it doesn't seem to crash in 1) unmodified saves, and 2) if I turn off the associated command on the ships that were running it.

I haven't tried it for more than a couple minutes, but if it will run for an hour or something crash-free, that's gotta be the cause, somehow.

* (I'd been running the script, to my knowledge without changes, for hours beforehand with no issues, but that's the only possible cause I've found so far. I checked the script and there don't seem to be any infinite loops, save for the main loop (with "wait randomly" in there, and @ instructions like flying to stations), no divisions over zero, nothing that could possibly be an issue... odd)