Sub UseMsoAnimEffectPlayVideoFromBookmark()

Dim oShp As Shape         ' Shape trigger
Dim oShpMovie As Shape    ' Media shape

With ActivePresentation.Slides(1).Shapes
    Set oShpMovie = .AddMediaObject2("C:\Videos\sample.wmv", False, True)
    Set oShp = .AddShape(msoShapeRectangle, 10, 10, 100, 50)
End With

With ActivePresentation.Slides(1)

    ' Create three bookmarks on the video at desired points

    Call oShpMovie.MediaFormat.MediaBookmarks.Add(10000, "Bookmark A")
   Call oShpMovie.MediaFormat.MediaBookmarks.Add(20000, "Bookmark B")

   Call oShpMovie.MediaFormat.MediaBookmarks.Add(30000, "Bookmark C")

    ' Create an animation sequence to start playing playing from the second bookmark

   ' When you use the msoAnimEffectMediaPlayFromBookmark enum value PowerPoint assigns 

   ' the first bookmark as the starting point for the video, to change that you need 

   ' to edit the bookmark property

    With .TimeLine.MainSequence.AddEffect(oShpMovie, msoAnimEffectMediaPlayFromBookmark)
        .Behaviors(1).CommandEffect.bookmark = "Bookmark B"
   End With
    

    ' Create a shape trigger to start playing from the third book.

   ' Don't set the bookmark name in the AddTriggerEffect call, it will be ignored

    With .TimeLine.InteractiveSequences.Add.AddTriggerEffect(oShpMovie, _
                    msoAnimEffectMediaPlayFromBookmark, _
                    msoAnimTriggerOnShapeClick, oShp)
            .Behaviors(1).CommandEffect.bookmark = "Bookmark C"
   End With

End With

End Sub