Unable to view web UI after running Docker-Compose from tutorial

Graylog Central (peer support)
4 
      - GRAYLOG_HTTP_BIND_ADDRESS=127.0.0.1:9000
      - GRAYLOG_HTTP_EXTERNAL_URI=http://127.0.0.1:9000/

But your docker Container is configured to run in 127.0.0.1 the docker-compose from the documentation is created to make Graylog run and reachable on localhost on your desktop for example. You need to adjust the settings to your local needs.