Is there a list anywhere of the keyboard shortcuts in Raspbian? There's nothing obvious in the documentation that I've found. I've established that Cmd+r opens starts 'run' and Cmd+e opens an explorer window. Are there any others?
The configuration file is the lxde-pi-rc.xml that contains different keybind keys. Just add one that you want in this file following the examples.
I found the lxde-pi-rc.xml but in my case it was in a different path: /etc/xdg/openbox/lxde-pi-rc.xml
I guess that in the recent versions they changed the path.
I hope it can help you.