I need your advice on this issue.

I have developed a workbook consisting of 40 sheets. They are grouped and
hidden at startup and the code determines which are made visible.
The workbook was developed using a screen resolution of 1280 x 768 and all
sheets display properly at zoom 100%. Others will use this app so I put in
code to check their resolution settings and then set the proper zoom level.
I store the zoom as a global variable. In Workbook_Open I apply the zoom
using ActiveWindow.Zoom = 112. This is great for the splash sheet which is
active but as soon as I go to another sheet the zoom goes back to 100%. Does
each sheet create a new activewindow? I tested by displaying the name of the
activewindow and it is always the name of my app so I think not.
I do not want to have to put code into all 40 sheets (I have stayed away
from putting any code in sheets). Is there a way to intercept (event) when a
sheet on the sheettab is activated so I can put the code in the event? How
is this normally done?

Thanks.

rick