Currently, the URLs for images are referenced by a dynamic code '&pos=#'. The most recently submitted image is assigned to #0, second most recent #1, and so forth. This means that when a new image is submitted, all the images get a new url. So the image with &pos=0 in the url becomes &pos=1, and so forth. This means that you cannot reasonably link to images, since any new submission changes what image the link goes to.
I think a better system would assign &pos=0 to the first image submtted to the gallery, then add from there. That way the URLs don't change.
Perhaps such a change is unfeasable, and not a large enough issue to make it worthwhile to address, but I think it's a major limitation on the way the system currently works, it makes links to any images almost impossible.
This is under consideration.... though not the way you are proposing but using pid(s) in the URL.