Pretty close - end time should be disabled whenever the end time is initially reached (so that if the user decides to 'play' again after the video ends, it will continue where it left off). It start time should really only effect the default start time. If the user decides to place the cursor anywhere else in the video, the video should play without problems. However, (just to be clear) the highlighting of the original start/end time should always remain on the video as the author originally specified.