Admitted, I've done some icon swopping in the past (using Candybar and IconBox). When updating from SL to Lion, I had issues with a few default icons. Upon launching IconBox, all the icon wells were marked in red, and after hitting the Restore button, all was well again to system resources. Today, after updating to ML, my Open Folder icon is missing. So if I select a folder (in Column view), the folder icon simply disappears leaving an empty space. IconBox again showed all wells in red, so I hit Restore - without result this time. When I apply any custom icon to p.e. the Generic folder, I get this one to both folder and selected (open) folder. Can anybody help me out on this strange behavior?