The following VBA example creates ellipses at four corners of the bounding box of the first selected object and in the center of the object.
Private Sub DrawEllipse(s As Shape)
ActiveDocument.ActiveLayer.CreateEllipse2 s.PositionX, s.PositionY, 0.1
End Sub Sub Test()
Dim s As Shape
Set s = ActiveShape
ActiveDocument.ReferencePoint = cdrTopLeft
DrawEllipse s
ActiveDocument.ReferencePoint = cdrTopRight
DrawEllipse s
ActiveDocument.ReferencePoint = cdrBottomLeft
DrawEllipse s
ActiveDocument.ReferencePoint = cdrBottomRight
DrawEllipse s
ActiveDocument.ReferencePoint = cdrCenter
DrawEllipse s
End Sub