Private Sub Frame1_MouseDown(Button As Integer, Shift As Integer, X As Single, _
  Y As Single)
 
  Dim Idx&, Rad!, DX!, DY!
 
  For Idx = Shape1.LBound To Shape1.UBound
    With Shape1(Idx)
      Rad = IIf(.Height < .Width, .Height, .Width) / 2
      DX = .Left + .Width / 2 - X
      DY = .Top + .Height / 2 - Y
      If DX * DX + DY * DY <= Rad * Rad Then
        MsgBox "Mausklick auf " & .Name & ":" & Idx & ":"
      End If
    End With
  Next Idx
 
End Sub

Gruss,

Zardoz