See the Pictures section for instructions. All stories are discussion group messages. A story is a special type of discussion group message. Marking a message as a story means you want it to be public. Manila site contents are all stored in the discussion group.
Pictures are just discussion group messages that have a picture attached.
You can see a ranking of most-read pages. Here's an example . See Multiple News Days for a HowTo for this feature. There's a HowTo and a reference guide that describe the format and how to use the feature. Some things are beyond Manila's control.