The container image consists of the Ember app and a nginx proxy that will serve the app and proxy the requests to your MaxInfo JSON listener. You're going to need to set that up, checkout the MariaDB knowledge base for that.
To give it a quick whirl, you'll need to run your container with an environmental variable set that is the IP:PORT of your MaxInfo listener like this:
docker run -it --rm -e MAXSCALE_MAXINFO_JSON_LISTENER_TCP_ADDR=10.190.0.5:8003 -p 9090:80 skord/maxpanel
The above command will run a the image, deleting it when it's done with the MaxInfo backend of 10.190.0.5:8003. The port the app will be available on is 9090. Feel free and map that wherever you like.