I think you might be too. Here's another screenshot of mine which shows you the first identity I set up (AndrewBrazieriMac) and as you can see, just iike you, it hasn't given me permission to access those files. 'Andrew' was created when I did the migration. IIRC it is important that the files are in the right Identity. i.e. - the User that has the little house icon against it because this is your default identity. I think a quick chat in the shop or a call to Apple support should straighten this out for you.