Step 4, adjust the settings for your feeds (Event Wall Feeds).
Comments Visibility To Public
Allow public users to see comments posted by invitees (default off)
Photos Visibility To Public
Allow public users to browse photos posted. ( Default is off )
Comments Visibility To Guest
Allow guests to post and browse comments.
Photos Visibility To Guest
Allow guests to post and browse photos posted.
Public Upload of Comments
Allow non-invited guests to write/edit/delete comments.
Public Upload of Photos
Allow non invited guests to write/edit/delete photos.
Comments Auto Approval
Puts all comments posted (invitees or public) on auto-approval (default off).
Gallery Auto Approval
Puts all photos uploaded (invitees or public) on auto-approval (default off).
Slideshow Settings
Slide to switch on slideshow function and select the album to be played.