Once you have edited you video then using the windows media player ocx
enter this code

Private Sub WindowsMediaPlayer1_MarkerHit(ByVal MarkerNum As Long)
If WindowsMediaPlayer1.Controls.currentMarker = 1 Then
MsgBox "Your video marker has hit 10 seconds"
End If
End Sub

If you have more than one marker use (currentMarker = 2) & so-on

Have fun & let me know how you get on

Regards

Paul