With the exception of Global Hotkeys in Windows, then all input is directed to the current Active Window. If it doesn't have a handler for it, then that input can be passed up to a parent process, culminating in the Operating System, and if there are no handlers found, the input is chucked, usually with a default windows bong noise to indicate invalid input, although sometimes not if that input is swallowed (mouse input usually is NOT passed up to parents for obvious reasons - it makes no sense to do so)***.

So, unless you can make HotKeyNet register a Global Windows hotkey, you'll be SOL from grabbing input from any random process, unless HotKeyNet happens to be the parent process, and it wont be a parent of the desktop.




*** this is a simplification to something that is more easily understood.