How to customize the Windows mouse button to open Greenshot function?

Question

I use the "Capture Region" function in Greenshot a lot. Is it possible to customize the Windows button to open the "Capture Region" function? The Windows button opens the start menu by default.

I found this question, where redefining it's behavior is done, but I can't find a way to do exactly what I want.

Needless to say, the Microsoft Mouse and Keyboard Center is of little use.

Note: I don't want to open the Program, only the function "Capture Region". This is because Greenshot is already running in the background, thus opening it again will cause errors.

Is what I want possible? And if so, can anyone give me some pointers as to how I can make this happen?