Hello Luis,
I replied to your email to us and am posting my reply here as well.
You can use the Hauptwerk master couplers to add coupler functionality to sets that do not have them. Look under View | Large floating control panels | Master Couplers. Then you can assign any MIDI switch to control them (right click on the master coupler buttons and choose Auto-detect). If you have extra keyboard keys then you may use those if you wish (just be sure to choose the option to toggle the state of the switch during auto-detection).