Hello
These fields, actually, not being used in frontend of the extension. It is just there to allow storing that data and use it in layout override if needed, so we do not enable that fields in new version (unless for existing documents having data for these fields)
If you need it, please get the attached file, unzip it, upload the received file to administrator/templates/atum/html/com_dms/document folder (template override) and these fields will be available
Regards,
Tuan