The CenterDistortion method centers a distortion effect in its shape.
Examples:
The following VBA example centers all distortion effects on the page.
Sub Test()
Dim s As Shape, eff As Effect
For Each s In ActivePage.Shapes
For Each eff In s.Effects
If eff.Type = cdrDistortion Then
eff.Distortion.CenterDistortion
End If
Next eff
Next s
End Sub