Code:
$NewCellMDN = $oVisio.ActiveWindow.Page.Shapes.ItemFromID(330)
$NewCellMDN.Move(-0.5,0.3)

Should be
 Code:
$oVisio.ActiveWindow.Select($oVisio.ActiveWindow.Page.Shapes.ItemFromID(330), 2)
$oVisio.ActiveWindow.Selection.Move(-0.5,0.3)

Based on the Macro.
visSelect = 2 according to Microsoft