technours wroteWhat is the actual/current/proper way to properly start the server
There is no specific "proper" way ...
technours wroteIs the GUI even supposed to be used to start the server
It is suitable if you run with privileges.
technours wroteWhat exactly is the use of the OVPN service? It does not seem to do much, even when started
Check your log for errors.
To use the service to start OpenVPN with a password protected key you will need to add:
management 127.0.0.1 {port}
management-query-passwords
to your server config.
You then need to connect to the management interface with a telnet client and enter:
password 'Private Key' {password}
You can then disconnect from the management interface.