VBA I have written for PowerPoint includes methods to help with the design of slides, which I converted to an add-in, and to dynamically change Active X components on a slide, during a presentation, which is attached to the actual slide.
I guess you may have tried to add Active X to a slide (like a scroll bar for example).
However, I could not for the life of me think of how to start them up automatically. I’m not sure you can (but stand to be corrected).
This link talks about this very issue: click here
I have not tried it, so obviously cannot endorse it in any way. May be worth a look though.
Don't forget that using an add-in means the effects you will get will only happen on a computer with the add-in. Stand-alone code "in" PowerPoint should run on any computer.