If you are passing an AAF to the grade and you are only offlining then colour space isn't really an issue. Unless you have a P3 colour space or better then you need to work in rec709 Avid knows the source footage has a larger re 2020 cour space so it's adding colour adapters to bring rec2020 to rec709. I certainly wouldn't rely on VLC as

On my current system that colour workspace regularly breaks and I have to restore to default.

The workspace has probably been corrupted. Go to windows workspaces and then reset the currect workspace.

I've not heard of this before I'm afraid. There are other Catalina users sucessfully running 2022.4 so there must be something "different" about your Mac setup. What that is I have no idea. I'd try a fresh OS install onto an external drive and boot to that and then try a fresh MC install. If that still has the same issue then it

MC will use the GPU to render effects if it can (and you've not disabled it) In the past Avid used to test which graphics cards and drivers worked and only those GPUs would be enabled. But that changed a while back and now Avid allows all GPU and driver combinations to work unless its listed in the DisqualifiedGpuBoards.txt file. So I'd suggest

I have had linked drives not show up if they haven't woken up when MC launches. A lot of drives go to sleep or only "wake" up when they are accessed. If I launch MC with linked media on a drive thats not connected my media is offline. Mounting the drive mostly doesn't restore the links as MC seems to have learnt they aren't there

I never ever use linked media for any project that going to run over more than one session. It's just not as stable as Avid media. Avid media stability is one of the key Avid strengths and using linked clips you forgo that. So I link and consolidate or transcode.

Have you tried creating fresh user settings and then try linking again. It's clearer to call this ingesting (that covers import and linking) Calling linking importing when imports a different function is confusing.

So instead of import setting change the import settings. (in source browser with link radio selected click the gear icon. For clips already linked in its not split. It's right click. Modify then multichannel audio.

It may EU the but 16GB is the minium RAM recommended for MC. You may find it a problem as your project grows.