Your code that depends on the OnSlideShowPageChange( SHW as SlideshowWindow ) event works when run from within VBA or when you launch the presentation from within PowerPoint, but not when you start the show by doubleclicking the icon for the PPS or PPSM. The slide show launches normally, but the code in your OnSlideShowPageChange subroutine never runs.
Solution
Add an Active-X control (from the Developer tab) on first slide (drag it just off the slide if you don't want it visible during the slide show).
This forces VBA to initialize when the presentation starts, so the event gets triggered and your code runs.
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