@cenriq:
Is there any way to do remote administration on the system? That's what I am searching on now. Thaks for your support.
As dotdash stated, enable SSH and HTTPS under Settings->Advanced in the menus.
What he didn't mentioned was that you MUST add firewall rules on WAN tab to allow incoming connections on these ports. To reduce SSH brute force attacks, you might want to change the default SSH port from '22' to say.. '222'.
If you do not want to reveal HTTPS on your WAN, you can always do a SSH tunnel socks proxy on the client then access the HTTPS webgui via the LAN IP.