This story was created using te link www.musicosity.com.au/node/add/story?og_group_ref=458453
We will need a block for creating content, with links that add arguments/tokens to the URL string i.e. "og_group_ref" which is the audience reference field shared by content types that are postable in groups, and the nid of the group to be appended to the end.
This link is on the ticket http://www.musicosity.com.au/help/entityreference_prepopulate/README.txt
Also the link to OG documentation is on the ticket - this explains how to set up an OG using panels.
Groups audience: