There is no functionality to show their stream from Facebook or Twitter on their profile or in CB Activity. No such feature is planned. CB Connect is strictly for login and registration with various providers.
In addition I can't get (eg.) Facebook ID to show up on user's "profile edit page" to let them type in their ID.
You can not edit the provider fields in profile edit. Those are set by CB Connect after they have been verified. Backend edit of them is for management purposes only, but should be left alone typically. A user needs to link their existing account using the Link button in your CB Login module if they want to be able to login with a provider account.