Use plugin with Twenty Thirteen theme

You go to Backgrounds menu option (the url is /wp-admin/edit.php?post_type=cpt_background ) and you create as many backgrounds as you want.

Where are you trying to add the featured image?

Hi, thanks for the super fast response – I have got it to work now, it was me being stupid!

thanks

Glad to hear that. ??

A review would be appreciated!
https://www.ads-software.com/support/view/plugin-reviews/full-screen-background-images