Passing field from page to content pane

I have a content type with an entity reference field (its a groups audience field - og_group_ref)

I want to put a content pane on this page which shows results for the group that the page is associated with..

How do I pass this field (og_group_ref) in to the pane as an argument?

the closest I have come is using the info I was given here - https://drupal.org/node/2140423

It seems I am nearly there but need some help with the pane..

I thought it would be easy enough, but I'm stumped?

Can anyone give me a pointer?