Although it is not possible to export all contacts from Roundsman, it is possible to export contacts who have agreed to marketing contact. In order to do this:
Open the Customers submenu
Double click Export GDPR Contacts
Tick Live customers only if you only want active customers
Tick the desired contact preferences; at least one must be selected.
Select a Module; not doing so will result in an error
Click Browse and set a location to save the export file to. Not setting a location will result in the export completing with no file produced.
Click OK
On completion the file will be saved at the supplied location for retrieval.