I don't remember exactly anymore but reading my blog entry you linked it says you shouldn't use Anonymous:
"Additionally there are a couple of security related settings which are important to understand. First of all you need to assign access to the document with the application keys to the ID with which you signed the two NSFs. In the screenshot above I've entered both OpenNTF servers and my own user ID. When you use the web UI to do this these names are added to the document in an authors field and a readers field.
In the last step you need to configure the ACL of the security store. Anonymous must not have access to this database. All users who you want to be able to use the Social Enabler OAuth functionality need to have author access. This is so that their user keys can be stored in this database so that they only have to do the OAuth dance once. "