Thumbnail of galleries in Lightbox

I have been breaking my head the last few days trying to find a solution for creating multiple galleries on one page with a single image thumbnail representing one gallery (of x images).

See example here:
Joorang theme
When you roll over the image it tells you how many images are in the gallery.

Does anyone know how this can be done??

ANY help would be SUPER appreciated!!

Thanks in advance!

P.S. I am using the Shaken Grid theme and would like each photo on each post to act as a thumbnail and open a separate gallery in lighbox/colorbox.

Right now, what it does is opens all the images in colorbox, from all the posts.