Typically XML Data custom fields are created for UTA level 1, 2 or 3, (e.g. a grant application) or they are created for organizations. To create a XML custom field:
#Navigate to the desired place, where you want to create the XML custom field (e.g. the UTA level 1).
# Click the '''New Field''' (+) button.
# For Field Type select '''Special - XML Data'''.