I've got this error on load:

Failed to load mods: Error while loading recipe prototype "electrochemical-science-pack" (recipe): Recipe has invalid main product acidic-electrochemical-science-pack. The product does not exist in the recipe product list.
Modifications: ○🌐Corrundum › Challenging pack logistic › xyrc's K2SO Enhancements › Science group › Rigor Module › Cargo Crates › Razi Protocol

Then it asks me to disable Corrundum (1.0.44), harder-pack(0.3.6), xy-k2so-enhancements (0.6.2), science-tab (1.9.0), rigor-module (0.3.6), cargo_crates (0.10.1) and razi-protocol (1.0.4)

I've got this error on load:

Failed to load mods: Error while loading recipe prototype "electrochemical-science-pack" (recipe): Recipe has invalid main product acidic-electrochemical-science-pack. The product does not exist in the recipe product list.
Modifications: ○🌐Corrundum › Challenging pack logistic › xyrc's K2SO Enhancements › Science group › Rigor Module › Cargo Crates › Razi Protocol

Then it asks me to disable Corrundum (1.0.44), harder-pack(0.3.6), xy-k2so-enhancements (0.6.2), science-tab (1.9.0), rigor-module (0.3.6), cargo_crates (0.10.1) and razi-protocol (1.0.4)

After troubleshooting, I removed "harder-pack" aka "Challenging pack logistic" (not sure where I picked it up, must be a dependency) and I got a new error:
Reached id limit for collision-layer. The game can't contain more than 55 instances of this prototype due to hardcoded limits of the engine. See the log file for more detail.

The log has the following listed:

48.637 Info PrototypeList.cpp:85: collision-layer counts:
48.637 Info PrototypeList.cpp:87: Cerys-Moon-of-Fulgora: 2
48.637 Info PrototypeList.cpp:87: Constructron-Continued: 1
48.637 Info PrototypeList.cpp:87: Krastorio2-spaced-out: 2
48.637 Info PrototypeList.cpp:87: RenaiTransportation: 2
48.637 Info PrototypeList.cpp:87: SpidertronEnhancements: 1
48.637 Info PrototypeList.cpp:87: base: 24
48.637 Info PrototypeList.cpp:87: cargo-ships: 2
48.637 Info PrototypeList.cpp:87: carna: 2
48.637 Info PrototypeList.cpp:87: cloud-city: 3
48.637 Info PrototypeList.cpp:87: combat-mechanics-overhaul: 3
48.637 Info PrototypeList.cpp:87: dea-dia-system: 2
48.637 Info PrototypeList.cpp:87: gleba-water-cane: 1
48.637 Info PrototypeList.cpp:87: linox: 2
48.637 Info PrototypeList.cpp:87: maraxsis: 6
48.637 Info PrototypeList.cpp:87: pelagos: 1
48.637 Info PrototypeList.cpp:87: planet-rabbasca: 1
48.637 Info PrototypeList.cpp:87: planetaris-arig: 1
48.637 Info PrototypeList.cpp:87: quality-seeds-fork: 1
48.637 Info PrototypeList.cpp:87: rubia: 1
48.637 Info PrototypeList.cpp:87: wooden_platform: 1
48.647 Error ModManager.cpp:1767: Reached id limit for collision-layer. The game can't contain more than 55 instances of this prototype due to hardcoded limits of the engine. See the log file for more detail.

I'll keep working on it.

I was able to move past the above one when I remove combat-mechanics-overhaul (which I added manually as a recommended mod of this one) but got the error I will post below. I then I disabled all other mods to except this one to try to isolate and I still get this:

Failed to load mods: Error in assignID: item with name 'kr-rifle-magazine' does not exist.

Source: corrosive-firearm-magazine (recipe).

Followed by reset requests for Pelagos 0.56.1, nulls-k2so-tweaks(1.19.0), castra (0.5.4) and rigor-module (0.3.6).

I'll stop here for now as everything else is excluded;

Hey thanks for the report love that people are giving the mod a try and I've been trying to work on bugs and iron out kinks so I really appreciate it!

I looked into it and honestly I should have removed Combat Mechanics Overhaul anyway! Because K2SO basically implements exactly what that mod adds already! I've corrected this and updated the mod! Thanks! Tell me how the run goes.

Just FYI, I have confirmed that after the patch I am still getting the above corrosive-firearm-magazine recipe error.
I also figured out that it was the Planet Lignumis that was the blocker, effectively making it an incompatability with your modpack because its own requirements (mostly wood related recipe changes, and then additional wood support to add wood to Vulcanis, Fulgora etc) was too many collision layer IDs when presented alongside the requirements for your modpack. Disabling it is essentially required for the current setup.

Is there anything you can do about the corrosive-firearm-magazine? I haven't done Pelagos yet, but it is in the Mod List and comes from there.

If it's at all helpful, I experimented and removed Pelagos from your required list then disabled it. I then get a new error about barreling machines having an issue, so not sure what is up:

Failed to load mods: barreling_machines/data-final-fixes.lua:24: attempt to index field 'cargo-crate-titanium-barrel' (a nil value)
stack traceback:
barreling_machines/data-final-fixes.lua:24: in main chunk

Mods to be disabled:
• barreling_machines (0.1.5)

Thanks for digging deeper. I think there are three separate things happening here.

The Challenging Pack Logistic / harder-pack issue looks like it changes Corrundum’s electrochemical science recipe in a way that xy-k2so-enhancements does not expect, so I’m not going to list that as supported for now.

The collision-layer issue is unfortunately a Factorio engine limit. I removed Combat Mechanics Overhaul from the recommendation list, and I’m also marking Lignumis as incompatible for now because the full pack is already too close to the 55 collision-layer cap.

The corrosive-firearm-magazine issue is one I can patch. nulls-k2so-tweaks upgrades Pelagos’ corrosive ammo to use K2 rifle magazines, but those magazines only exist when K2SO’s realistic weapons are enabled. I added a compatibility fallback so if kr-rifle-magazine does not exist, the recipe uses firearm-magazine again.