One issue I can see is you have a hyphen in your channel name ‘rig-test’. I did the same thing initially (think I even used the exact same name), the channel name has to be alphanumeric.
Once you change that you will also need to delete your browser’s localstorage because stuff like the token and channel name for each panel is stored there so just changing the command line argument isn’t enough.
Also in mine I used my username for the OWNER_ID rather than the userid which it looks like you are doing. From briefly reading the code it looks as though you need to use the same in both the rig and backend so maybe try using your username for both?
Also you are probably aware and it probably isn’t a big deal for your test project but you shouldn’t post your extension’s secret