Hi, I've searched but have found no answer... I want to have the medium sized images open up in a pop up window from the main thumbnail display. This pop up window would appear like the image I have attached... Do you know how to achieve this?
Making the full-sized image display when the thumbnail is being clicked is being discussed in some mod and plugin threads (e.g. "Highslide (Skip Intermediate Page and show full image ) (http://forum.coppermine-gallery.net/index.php?topic=36558.0)", "LightBox JS for Fullsize Popup Image (http://forum.coppermine-gallery.net/index.php?topic=35539.0)" or "from thumbnail to full-size pop-up (skip intermediate page) (http://forum.coppermine-gallery.net/index.php?topic=34360.0)" and some others). However, none of them will display the number of details you ask for. In your case, I suggest changing the link that points to displayimage.php to open in a pop-up instead of the same window. Then modify the intermediate image display and remove the stuff you don't need.
However, I ask you to review the whole idea thoroughly: most users hate pop-ups, and many have pop-up blockers enabled.