No light box effect in `nextgen-gallery` ..

Hi,
I am working on the website http://floodreliefpakistan.com/, I have installed the Nextgen Gallery both for a Gallery and Slide show effects. To my surprise I am not getting the `lightbox’ when I click on any of the images in the gallery. I am sure I have done all the things right but looks like might have missed something wrong, I would appreciate a quick response to help me resolve this issue and set up the gallery, like here on the example page: http://nextgen-gallery.com/gallery-page/
TIA