I wanted to take a close-up portrait, so I changed my antialiasing setting in Preferences, something I hardly ever do, and the viewer crashed as soon as I clicked OK to commit the change. On logging back in, I found that the change had been made, so I took my shapshots, and then went to change my antialiasing setting back to my normal x2 setting. Again the viewer crashed as soon as I committed the change. This is obviously not a high-impact problem, since antialiasing is not a setting that one changes all that often, but I thought I'd report it.