You can bulk import actions from a CSV file by selecting the Device Interfaces à NetworkThermostat à Import Actions option in the menu.
You will be presented with a dialog to select a CSV file to import.
Make sure your CSV file is formatted with the proper header fields as defined for the appropriate action. You can export the action to a file first to make sure you start with a valid format.
Important: Importing the actions via CSV import does not alter the Net/X network controllers and thermostats lookup list that is found in the Net/X Network Tab. There is also no validation between the imported actions and the lookup list.