Can there be an option to not have the external walls spawn and/or change the height to 1?

its already there

        "Arena Walls": {
          "Enabled": true,
          "Use Stone Walls": true,
          "Use Least Amount Of Walls": true,
          "Use UFO Walls": false,
          "Extra Stacks": 1
        },​

yes, just make "enable": false

Ah crap I just found them aswell haha! Thanks 

just tested and it seem the this option is not working with "0" . tried and still got  2 lvls of walls, also tried putting false and 0.0, but that just breaks the plugin

 "Extra Stacks": 1​

min is 1