Here's a workaround: just change the For each... Next to For... Next. The
following works:

Sub Play7()
Dim shpS As Shape
Dim N As Integer
For N = 1 To Selection.ShapeRange.Count
Set shpS = Selection.ShapeRange(N)
With shpS
Debug.Print shpS.Name
Debug.Print shpS.ControlFormat.LockedText
End With
Next N
End Sub

This solution to the problem seems general, so this bug doesn't seem so
critical as I originally thought.