Based on the latest comments on the RM, https://redmine.postgresql.org/issues/4320#change-16998 - Replaced server_manager.py on my Win 10 system - could login and run queries, etc - but eventually got "create_ssh_tunnel() missing 1 required positional argument: 'tunnel_password'",attached is the patch to fix the issue.
Kindly review and consider this for the upcoming release.