already did that
i hosted a non dedicated server with no addons and it still won't work.
Host a non-dedicated server and have people try to join it. After a while, quit Blockland and go to your Blockland folder, if you are a PC user, go to My Documents, Blockland. Using the default Blockland forums attachment's, attach your console.log file onto your post. I can see if I can find the problem through that.