Hi F77, long time no see!
You can indeed do what you want - almost.
You can build self documenting exports by adding the project and/or model name to the Page Header to be included whenever you export a Table or Summary to an Excel file. There are icons at the top right of the Page Setup dialog to insert these into the header for you.
It then becomes the page header on the Excel sheet and is visible only when you print it.
It shouldn't be too terribly difficult to write yourself a little macro, stored in the Personal.xls file, that you could attach to a toolbar icon which would copy the page header text into the property comments area. The macro could then, optionally, clear the page header.
In fact, it would be just like this:
ActiveWorkbook.BuiltinDocumentProperties(5) = ActiveSheet.PageSetup.LeftHeader
Dim iAnswer As Integer
iAnswer = MsgBox("Clear the page header?", vbQuestion + vbYesNo, "Please confirm.")
If iAnswer = vbYes Then
ActiveSheet.PageSetup.LeftHeader = ""
This seems to leave some font information in the comments box. A calculation or two could be used to strip that out if necessary.
Then all you need to do is add a toolbar icon and connect it to the macro. When you open a file exported by Monarch you just click your button to put the Monarch info into the comments box in the file Properties.
Does that help?