Add Timecode allows you to add a Timecode overlay to the video at the project, track, event, or media level. Adding it to the project is useful if you needed to give a client a video with continuous timecode so that they can make comments at particular times in the video and reference them by timecode. Adding it to a track will have the same effect as adding it to the project but it will only be visible when that track is visible.
Adding it to the events will cause the timecode to reset to zero at each event and adding it to the media will read the actual timecode from the recorded media (if any) regardless of the timeline position of the event that holds the media.
It does not synchronize audio and video files.
BTW, thanks for pointing out that it is missing from the documentation. I will make sure that it gets added.
VASST Trainer / Author / Software Engineer www.vasst.com