Ok, so I did this:
Type in my IP address in the address bar.
Clicked on UPnP.
And put a check on "Turn UPnP On".
Is that correct?
Well, go try it out on blockland.
(NOTE: An easier way to check if your server has ping.)
1. Go into "Mod Manager".
2. Search "Server".
3. Download the "In-Game Server Switch".
4. Go into "Options", "Controls", then scroll until you get a list called "Gui", then set the "Open Server List" to F4.
5. Start your game, and wait till you spawn, and open the Server List, and see if your up there.