I use WPSupersized version 3.1.5 with NextGenGallerie 2.0.0 both latest release on Chrome.
WP Supersized stopped loading a NextGen gallery after entering the ' sign in the description field of one of the images of that gallery.
After adding an image of zebra's to the gallery with the description Zebra's, Supersized could not load this galery. Simply changing the description to Zebra solved the problem.
Is this a known problem?