Global hook to listen to all keys pressed in Windows 8 - Store app

Hello,

In Win32API/.NET it's possible to register global key hook handler. So even if the app is not focused (but running in the background) the application can listen on keys pressed.

With Windows Store apps you can't control the life cycle of the application. You can have background tasks but they get 2 seconds of CPU every 15 minutes so I don't think this will work (But please correct me if I'm wrong here).

If this is not possible at all can I do the following:

Create Windows Store app that is a UI interaction layer with the application. Once the user downloads the app and the app starts for the first time it checks if given Windows Service is installed. If not it asks the user to download and install this Windows Service (that will be a global key hook handler).

Are there any restrictions on Windows Store apps when it comes to downloading and executing installer files from the internet?

Thanks for your help,

Marcin