I think those extra parameters in url (after-#) are generated to make that plugin work with browser history. I think the plugin doesn’t loading required javascript to popup full sized images. thats why it only updating url but not showing full sized image.
See the source code of page to make sure you’re loading all necessary JavaScript files.
NOTE – Some plugin uses javascript to show full image on same page (without refreshing it). So when you browse through different images the url remains same and if you want to view last viewed image the browser back button won’t work.
To make sure the browser back button work, the javascript add those extra parameters in url each time you open new image in gallery.