[Plugin: NextGEN Gallery] NextGen gallery thumbnails don't open up to larger images with captio

hi, i’ve entered my gallery on a post but the thumbnails are unclickable, usually they open up larger with the captions underneath and next and previous links etc, but now even if i hover over the thumbnailks nothing happens.

the ‘recent uploads’ widget of the ngg plugin works like it should so i can’t understand what can be wrong here. maybe i’ve missed a setting, i’ve tried thickbox and shutterbox but same behaviour.

my page:
http://www.artbyherbie.com/4093/project-management-ultimate-strength-and-fitness-nelson/

thanks for any help.