In order to do this you need to modify the XML file that is being read by the slideshow widget as well as change a couple of options in how the slideshow is being used. The two files that require modification are located in the NGG directory in your wordpress plugins directory (assuming you put it there) Here is what I did:
Find the nggwidget.php file and make these changes
- In function nggSlideshowwidget change the line that is
$out .= "\n\t\t".'sbsl.addVariable("linkfromdisplay", "false");';'
'$out .= "\n\t\t".'sbsl.addVariable("linkfromdisplay", "true");';
This tells the slideshow widget to jump to an assigned link as opposed to bringing up the next image. If you want the gallery to open in the same window and not a new window you can also add this line right below the previous line that you changed:
'$out .= "\n\t\t".'sbsl.addVariable("linktarget", "_self");';
Next find nggextractXML.php and find the line near the bottom like this:
echo " <location>".$siteurl."/".$picture->path."/".$picture->filename."</location>\n";
I added a new line after this to add the location of the gallery page to the XML file:
echo " <info>".$siteurl."/?page_id=".$picture->pageid."</info>\n";
The exact url you are looking for will depend on how you have your galleries setup. So in my case I want to direct the slideshow to a URL like the below in order to reach the gallery page for that specific image:
Let me know if it works for you.