Strange indeed!
Let me start off by saying the Windows hotkey idea didn't work. When I'm in-game they don't work .... errr. So I'm back to hoping we can resolve the issue with your application

I've just started a corp evaluation of a new AV solution, so tonight I will do more testing to see how it goes. As for CTRL+pgup/down ... your app takes the settings and does not change it. It just doesn't execute....
Just FYI, the hardware in question is a Lenovo W510 laptop. I may need to uninstall the Lenovo tools that allow for "Fn" keys to work ... I don't know?!
Frank