A family of Microsoft presentation graphics products that offer tools for creating presentations and adding graphic effects like multimedia objects and special effects with text.
Applescript aside, a non-activated copy of PPT that's gone past the end of the trial period will allow you to open presentations, view and print them but will not allow editing them in any way. That would almost certainly include changing slide show setting/advance mode, but I don't have a trial version to test with. Since you do, it'd be a good idea to see if you can manually make any of the changes you hope to automate.