This example moves node two in shape three on myDocument
to the right 200 points and down 300 points. Shape three must be a freeform drawing.
Set myDocument = ActivePresentation.Slides(1)
With myDocument.Shapes(3).Nodes
pointsArray = .Item(2).Points
currXvalue = pointsArray(1, 1)
currYvalue = pointsArray(1, 2)
.SetPosition 2, currXvalue + 200, currYvalue + 300
End With