MacBook can't run this game anymore

macOS utilizes the OpenGL graphics API whereas Windows & Linux system are able to use the Vulkan graphics API which is much newer & better than the very old OpenGL API. (API == Application Programming Interface.....utilized by program developers to communicate with other software like the OS & drivers to make programming easier & more consistent).

I'm glad it was such an easy solution. Thanks for sharing it with us here so that it can help others who find this thread.

Enjoy your new DLC.

DLC content may require increased system requirements above the requirements for the core game. Even a new game update or DLC content update can increase those system requirements....many times without any warning.

Unfortunately macOS is not an ideal for gaming since there are so many variations between various versions of macOS which makes it very difficult for both developers and users to figure things out. It is great when it works....

Check with the service you used to acquire the game and its DLC for support since they are the only ones who will likely have necessary information to assist you. Check the game's forums since there will like be some other Mac users with similar issues and possible solutions.

So I've had the opposite experience where it's only ever worked on Vulkan. Switching to OpenGL gets me nowhere sadly.

I was running CK3 with next to no issues on MacOS Ventura 13.6.7. Unfortunately, 2 days ago, I finally relented after a million reminders from my computer to update to Sonoma and it basically threw my whole computer for a loop and it took me the entirety of the day + 90min of apple care support to get certain basic functionalities (like moving files around) working again. It also has caused some weird stuff with iCloud which may or may not be interfering with CK3.

I performed a complete wipe of all Paradox related files on my computer (in Steam, in Documents/Paradox Interactive, and also the Paradox Launcher). Based on PDX online forums, apparently running stuff on Mac has been a known issue for a while, but it doesn't seem like anything has been done to fix it.

As a last ditch effort I followed the instructions here (adjusting for CK3 and not EU4), and eventually, I actually did have some limited success where CK3 did in fact load. However, that was short lived since by noon the next day, the game wouldn't load up past the screen where it says "Initializing Game" in the top left corner.

TLDR: I tried a few things, had some brief limited success, but ultimately there seems to be a direct issue stemming from certain PDX games not being able to run on certain recent MacOS.

[Edited by Moderator]

If you find an answer either way, please update your thread so anyone else who finds your thread may not have to do as much searching. Unfortunately games are the hardest apps to troubleshooting on any platform, but especially on macOS where support may dropped at any time for the reasons mentioned in my previous post.

Good luck.

Before this issue started I updated my OS could that be the issue?

Perhaps, but macOS updates are something the game developer has to keep on top of. I surmise they need to update it.

Where do I locate the place to make this change?