Removing the shortcut for "print screen" in the Gnome preferences works around this bug, at least so far as the up arrow key is concerned. After making the change, up-arrow moves the focus instead of invoking gnome-screenshot.
Obviously, this doesn't address the cause of the issue, but it may help to identify what is going on. -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]