Thanks for clarifying; yes, I get it...
Well, you could try using a USB Device Key Trigger but I have just experimented with that and couldn't (on first try!) get it to react in the expected way.
This discussion might be of interest: Feature Request: An Enhancement for Detecting Modifier Keys.
I have to say that I would go for an acceptable path of least resistance, for example, trigger the "help" image display with hyper-?. So I'll leave it to other people's ideas now. 