I would appreciate some help with te following issue:

I want the comments to be visible for all users, and I only want authenticated users to be able to add (not edit) comments (and create story content - not to edit own story content).

In the Permission settings for the Node module I only selected the 'access content' for anonymous user and authenticated users. All other boxes are empty.

Still, the comments don't show for anonymous users.
They only show for authenticated users, and authenticated users can edit their own comments,
and they can select their preferred way to display the comments and click "Save settings" to activate the changes, as I don't want hem to.