It looks like after setting up the network, you were going to setup a mux (putting info in for your stream) but the muxes configuration failed to load. This is likely due to their not being any muxes...I'll have to check if that's true.
My addon just makes part of the tvheadend interface available in kodi so you don't have to use the web interface. All normal tvheadend setup information should be followed.
The easiest way to setup IPTV channels is to use the IPTV automatic network. For this, the list of your streams are put into an m3u file that tvh can read in and automatically setup the muxes and services.
You can see an example file here: http://siptv.eu/lists/example.m3u
Download that file if you want to look at how it is made - or to test it, enter that url into an IPTV Automatic Network and see how it works. :-)
Once services are setup - the final step is to just map the services to channels and then you're reday to watch!