In SimpleViewer-Pro, each image is part of a single Flash presentation and is not simply displayed using a traditional HTML <img> tag (which is what Pinterest is likely to be looking for).
Even if you were to incorporate this script (which uses PHP to parse the gallery's XML file and include <img> tag entries for each image within the gallery's HTML page), you would not be able to select an individual image from within the Flash presentation.
You could try using the Mobile Player.
You can force SimpleViewer-Pro to display the gallery with the Mobile Player (using HTML rather than Adobe Flash Player) by setting the useFlash Embed Code Parameter to 'false' in your gallery's simpleviewer.load() line.
If you simply need a direct URL to an individual image within a gallery, this can be achieved using the SimpleViewer-Pro API.
Please see the 'Direct Linking' example here.
SimpleViewer Support Team.