You have to be up to date on the Necrobot side (master or maybe latest release).
In the Visualizer, the url on the config page should match the port you configured on NecroBot side (both have the same default).
Go to the release tab, grab the latest and just launch it.
Click on the small settings icon on the bottom right of the app.
The important thing is websocket url and port. Default is also bot default so it should just work.
You can also choose local for Pokemon name display.
npm i && npm start
