My colleague discovered an "interesting" error. When I use https the enclosed media displayed ok but the SVG graphic won't display on the web page. I switched to the http, and everything is displaying properly, and graphics from the template are present for a user..
If the page contains http and https content, web browser will block the http content. To avoid this I used this solution, recommended here.
There are any templates ready-to-use or best practices dedicated to the moodle?