Adobe Lightroom 3.6 (64 bit) for MacOS freezes when quitting, after browsing through many raw Nikon picture files. The problem is 100% reproducible: When looking at pictures, if you press right arrow to see the next picture while the "Loading.." message is still present, the "Loading..." message will then never go away. After this, when selecting Quit from the Lightroom menu, the application will freeze. The only way to proceed is to Force Quit. This problem is new and was introduced with the 3.6 update.