I want to purchase the upgrade license from cs5 to cs6, so that photoshop will recognize our new nikon cameras. d800 and d7100.
No problem. Just log on to your Adobe account, and do the deal.
But you don't absolutely need to do that to access your D800 NEF files. You can download the free DNG convertion app, and change the NEF files to DNG that will then open in CS5.
Retrieving data ...