MediaView.Duration (gb.media.form)
Property Read Duration As Float
Return the duration of the media in seconds.
Note: this value remains zero until the file is played.
Just setting the 
URL property will not show the media duration.
For example..
  MediaView1.URL = "/tmp/Media.mpg"
  Print MediaView1.Duration
  
  MediaView1.Play
  MediaView1.Pause
  Print MediaView1.Duration
Prints...
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