Since you are working with an object you are going to have to go with a Property Get and a Property Set. Try something like this instead.
VB Code:
  1. Option Explicit
  2.  
  3. Public Property Get Picture() As Picture
  4.     Set Picture = UserControl.Picture
  5. End Property
  6.  
  7. Public Property Set Picture(ByVal New_Picture As Picture)
  8.     Set UserControl.Picture = New_Picture
  9.     PropertyChanged "Picture"
  10. End Property
  11.  
  12. Private Sub UserControl_ReadProperties(PropBag As PropertyBag)
  13.     Set Picture = PropBag.ReadProperty("Picture", Nothing)
  14. End Sub
  15.  
  16. Private Sub UserControl_WriteProperties(PropBag As PropertyBag)
  17.     PropBag.WriteProperty "Picture", Picture, Nothing
  18. End Sub