Shortcuts Setup
For putting desired operations on fast buttons on POSX the setting is made in POSX Touch menu settings.
Option "Fast" is chosen:

And then the operations are set on fast buttons by drag and drop from lower panel to above one:
In case we want to remove operation from above panel we drag it down to below panel.
With click on "Save" button the changes are saved.
Shortcuts are set on a specific Document type for POSX in Document types Settings.