Remote control devices for Powerpoint use <PGUP> and <PGDN> to change slides. However if powerpoint does not have focus, then the slides won't change. This tends to happen especially with Presenter View in Powerpoint. The attached autoIT script detects <PGUP> and <PGDN> keys, detects if there is a presentation running, then transfers <PGUP> or <PGDN> to the presentation. If there is no presentation running then <PGUP> and <PGDN> function normally.
To make this run on startup, simply copy the .exe file to shell:startup