Fit picture to cell

Hi

I am using a dynamic range to determine what picture to put into a cell, and have used a macro to try and fit the picture to the cell which is

Public Sub FitPic()
 On Error GoTo NOT_SHAPE
 Dim PicWtoHRatio As Single
 Dim CellWtoHRatio As Single
 With Selection
 PicWtoHRatio = .Width / .Height
 End With
 With Selection.TopLeftCell
 CellWtoHRatio = .Width / .RowHeight
 End With
 Select Case PicWtoHRatio / CellWtoHRatio
 Case Is > 1
 With Selection
 .Width = .TopLeftCell.Width
 .Height = .Width / PicWtoHRatio
 End With
 Case Else
 With Selection
 .Height = .TopLeftCell.RowHeight
 .Width = .Height * PicWtoHRatio
 End With
 End Select
 With Selection
 .Top = .TopLeftCell.Top
 .Left = .TopLeftCell.Left
 End With
 Exit Sub
 NOT_SHAPE:
 MsgBox "Select a picture before running this macro."
 End Sub

BEFORE I GET A WARNING, THE POST WONT LET ME PUT CODE TAGS OR FORMULA TAGS AROUND THE TEXT???????

but this doesnt work? my cell has =ShowMyPic in it

Which is picking up the linked cell from a combo box

Is there a way i can get the picture to autofit the cell?