for register/activate (I tried this in version 5.4.8 and it works.)
find this file in your host:
wp-content/plugins/revslider/includes/operations.class.php
find this value in file;
version_info == 'valid' (file contains two pieces of this value)
to change value to this;
version_info == 'invalid'
(English is not my native language. I'm sorry about typos.)
This works! Thank you!