Hello,
Sorry to answer late on this post, i didn't notice as it grows ;) !
To make your application to have focus, you can communicate with the process that you made working ( with readyReadStandardOutput()....), then you can send kind of "events" to the app, and itself can then use activateWindow().
This is not a simple way, but as your simple try does not work, i have used this one, and at least it works.
altought the behaviour seems different on windows, it is still ok.
democrie