What platform are you targeting? That output is from my phone, but I develop for phone, tablet and desktop and planned on using this on all of them. Could you attach a sysdiagnose, report via feedback assistant and share the feedback number here? FB19592652 I hope I did that right, I've never directly pulled a sysdiagnose before ^^

Sure thing, I'll add that to the feedback. As far as I am aware, the only entitlement I'm using is iCloud documents, which is wired up to an iCloud container. The good news: I don't get the error on Mac, so I've been able to play around with things a bit more there. The project I'm attaching is a tiny bit more complicated now, but the base code I used for the example is still there.

I think this has been fixed in iOS 26 beta 9. The first time I ran it gave me an error saying it couldn't talk to my iCloud account, but the second time it reported back "ready" and gave me a url to save to.