Hi @thecashbag,
Wordpress requirement is 5.6 or greater, so it should work since the builder only relies on the resources provided by Wordpress. The one that is directly talking to MySQL server is Wordpress, and it only provides the API that theme and plugins use. Examples,
https://developer.wordpress.org/reference/functions/wp_insert_post/
https://codex.wordpress.org/Function_Reference/update_post_meta
And more…
The theme and plugin have no understanding of what or information of the database is being used, and it doesn’t matter as long as Wordpress database API and function works. All compatibility between database are handled by Wordpress.
Though, it could be possible that your MySQL upgrade is incomplete or without proper configuration/corrupted that even Wordpress is unable to handle. Example, http://blog.lavoie.sl/2014/12/mysql-57-and-wordpress-problem.html
That’s why some hosting provider mostly offers and install bundled of software that is already tested. I recommend staying for MySQL 5.6 for now. As upgrading my MySQL to 5.7 broke my entire system (host environment) too.
And please re-upload your video with MP4 format, it’s not currently playing on my end.
Thanks!