Resettable Runtime Counter
Runtime Counter: The Runtime Counter shows the time since the start of the session. The counter can be set back to zero with a simple double-click on the counter itself or by creating an IO event and selecting '/mxw/render/runtime' as receiver (the event can be activated, for instance, at the start of the playlist). (A)
For resetting the Runtime Counter with IO events check Tutorial Resetting Runtime Counter with IO Commands in Playlist.