I need to change the url of the courses, ( for SEO purposes I need it to be in Spanish ). I have followed all the steps I have read here, changin the curstomizer_class.php, but the url doesn't change. On the other hand if I try to change the course category in general settings > permalinks, it doesn't work, and it doesn't find the link of each course.
http://www.sparksconsulting.es/clientes/iedip/
Please make sure all your plugins and theme is updated to latest versions.
Now you don't need to put any code in the customizer plugin for course slug. Just go to settings->permalinks->course permalink base and click on custom and then change the slug and save changes. It works fine refer: http://prntscr.com/aczbwc