Hello all,
I’ve been in the same issue than most of you and searching for solution and attempt to fix the path as described via this page: http://www.nextgen-gallery.com/galleries-opening-lightbox/
I realized that my paths are just correct but some bugs somewhere forced me to put a fake path, changing the paths a little bit, Save and then put back the paths, Save again for it works again. Could be related to server-side WP cache but I did not have the chance to check that but this workaround works just fine for me so I just want to share with you guys.
Good luck!
