Thanks.
I left Kitematic and tried the way described in your link.
I made everything and at the very end I obtained the message “Successfully built” but when I try http://172.17.0.1:80 in Firefox I receive a “page not found” message.
In config.js I set 172.17.0.1 as MYDOCKERHOST and 80 as PORT. 172.17.0.1 is the IP address of my Ubuntu VM in the “docker0” network interface.