1. If you need to add more slides, then there are a couple of adjustments that need to be made.
Firstly, duplicate how many pairs of slides you want to add (this will include the buttons on the slides)
Now you need to change the number of slides that PowerPoint expects there to be. To do this:
Check how many slides there are, subtract 1, and half. Remember this number.
Double click on the button while NOT in slideshow mode.
In the window that opens, use the slider on the left to locate “Module 1” and double click on this.
In the fourth line change the number 50 to the number you calculated above.
Close the Visual Basic window to return to PowerPoint.