Here's the challenge.
The user's workbooks all rely on macros.
To simplify updating of macros and bug fixing all the macros are kept in a
central storage file.

"workbook A" has it's buttons linked to "Macro Storage" as does "workbook B"
etc etc
So when the user hits a button in "workbook A" it opens "Macro Storage" as
read-only and executes the macro.

The mods that I'm making require some coding to be added to the users
workbook. (Essentially a run-on-load subroutine).

When the mod runs from "Macro Storage" is there any way to create a
"Private Sub Workbook_Open()" in the users workbook and insert the code?

Thanks in advance.

Giz