How to move images in bulk from media library to Next Gen Gallery?

Hi,

I’m looking to use the Next Gen Gallery in some of my older posts that are currently in different galleries. How do you move images from the media library to the Next Gen gallery, or better still convert the current galleries?

Here’s a link to one of my posts with a gallery: http://www.enjoythejourney.org.uk/scuba-diving/

Thanks for your help

http://wordpress.org/plugins/nextgen-gallery/