Log into gportal. Once you are in click on the box to the left of the gear. Several tabs will appear at the top. Click on Basic Settings, the first option that appears is Server Name. Type in your name selection and save.
On the server Basic settings tab, navigate to Password. The admin password you enter (space under server password) is the password you use in game. Once you set this password. Log into the game on your server, bring up the settings menu. The tab to the far right is Server Settings. Select Make Me Admin and a popup will appear at the top of the page. Enter the password you set and then the Admin Panel will now appear in your settings menu. Hope this helps.