Error message : https://i.imgur.com/2zxu3UU.png

Modslist : https://pastebin.com/LfGmuhJW

Let me know what else I can provide to help troubleshoot

That's interesting...

I'm getting missing sound when loading sound library...

What version of K2 do you have?

K2 version : 1.2.25

Hm...
Has to be something with other mods... I just tested with 1.2.25 yesterday, and aside of the sound problem I spoke of yesterday, it worked fine...

ACTUALLY--I think I got it... One of the mods overrides / removes that specific ammo type...

That's gonna be fun finding which one is the culprit...

A new version is going up today... Hopefully this fixes some issues?

But I couldn't replicate your issue... When I installed the mods listed, I got this:
https://i.imgur.com/sPN9J0S.png

Edit: ... or maybe not?
No clue what's going on with uploading mod today... Will try tomorrow...

There's an option, default enabled, in Krastorio2 labeled "More realistic weapons". Inside the data, this is designated as "kr-more-realistic-weapon". That ammo category, as well as "pistol-ammo" and "rifle-ammo", are only inserted if that setting is enabled. The insertion of that category is locked behind an if krastorio.general.getSafeSettingValue("kr-more-realistic-weapon") then conditional in Krastorio2/prototypes/categories/ammo-categories.lua.

There's an option, default enabled, in Krastorio2 labeled "More realistic weapons". Inside the data, this is designated as "kr-more-realistic-weapon". That ammo category, as well as "pistol-ammo" and "rifle-ammo", are only inserted if that setting is enabled. The insertion of that category is locked behind an if krastorio.general.getSafeSettingValue("kr-more-realistic-weapon") then conditional in Krastorio2/prototypes/categories/ammo-categories.lua.

Ah, thanks for that!
I have a different approach for this in my devel version: Just don't load the anti-material (gun/ammo) if the ammo category isn't present... I never realized there's an option to actually change weapon / ammo type completely.

Ya, the typical approach for that type of compatibility seems to be conditioning loading a def on that def actually existing. Checking the setting that the def is behind works, I guess, but it depends heavily on Krastorio2 not changing the linkage between that setting and the def in the future, of course.

Anyway, my short-term fix was just to turn that setting on. I'd disabled it initially because it seemed like a bother and that it'd be more likely to cause compatibility issues, but tbh it's actually a pretty good change, and I've yet to run into compatibility issues with it.