1. checkbox required fields is not working even on wordpres 2017 theme : https://buddypress.trac.wordpress.org/ticket/7845#ticket
2. Reinstalling emails from tools-> buddypress -> not importing some emails which includes activation email even on wordpres 2017 theme :
Quick fix : https://wplms.io/support/knowledge-base/activation-email-not-importing-on-re-installing-buddypress-emails/
3. update to vibe course module 3.5.1.1 .