The simplest instruction to show images is the following
ActiveWindow.ShowPicturePlaceHolders = False
and to hide is:
ActiveWindow.ShowPicturePlaceHolders = True
A more complex macro to hide/show, that also will start only if a document is open, is the following:
If Application.Documents.Count > 0 Then
Status = .ShowPicturePlaceHolders
Select Case Status
.ShowPicturePlaceHolders = False
This_Button.State = msoButtonDown
.ShowPicturePlaceHolders = True
This_Button.State = msoButtonUp
MsgBox "No documents open"
Just copy it into a macro and assign the macro to a button in your custom toolbar.
Pressing the button will show/hide the images.
[Edited at 2005-12-22 12:47]