XL 2010 VBA - Mettre une image intégrée en arrière plan

Sub SelectionPDF()
Dim Target As Range

ActiveSheet.Unprotect Password:="."
    Set Target = ActiveCell ' <-- cellule où sera déposée le Pdf
    With Application.FileDialog(msoFileDialogFilePicker)
        .InitialFileName = ThisWorkbook.Path & "\"
        .Title = "Sélectionner le fichier PDF"
        .AllowMultiSelect = False
        .ButtonName = "Sélection Fichier"
        With .Filters
            .Clear
            .Add "PDF", "*.pdf"
        End With
        If .Show Then
            Application.ScreenUpdating = False
                With ActiveSheet.OLEObjects.Add(Filename:=.SelectedItems(1))
                    .Name = "PdfImg"
                    .ShapeRange.ZOrder msoSendToBack
                    .Left = Target.Left
                    .Top = Target.Top
                    ' Proportions du PDF : à ajuster manuellement
                    .Width = Target.Width * 3.385
                    .Height = Target.Height * 16.925
                End With
            Application.ScreenUpdating = True
        End If
    End With
ActiveSheet.Protect Password:="."
    
End Sub