There are new documents regarding EUDAMED and actor registration. You can find all of them on the dedicated EC website.
https://ec.europa.eu/health/md_eudamed/actors_registration_en
EUDAMED guide to actors management
https://ec.europa.eu/health/sites/health/files/md_eudamed/docs/md_user_guide_actor_module_en.pdf
EUDAMED Actor roles and your SRN format.
https://ec.europa.eu/health/sites/health/files/md_eudamed/docs/md_actor_roles_srn_en.pdf
The required mandate for non-EU EUDAMED registrations, this is the summary information
https://ec.europa.eu/health/sites/health/files/md_eudamed/docs/md_mandate_summary_en.pdf