When you lock your root htaccess file on the BPS Pro > B-Core > htaccess File Editor tab page your root htaccess file permissions are changed (locked) to 0400 file permissions. Your wp-config.php file permissions will also be changed (locked) to 0400 file permissions. You can unlock your wp-config.php file on the BPS Pro > F-Lock > File Lock tab page. Most likely the WP Rocket check and error message can be ignored and/or dismissed if the check is just a general check that checks if the root and wp-config.php file permissions are not writable, locked, 0400. I assume the WP Rocket file permissions check is only checking if the files are writable and not also checking if WP Rocket code exists or does not exist in these files. So you can either just keep these files unlocked or if the WP Rocket check and error message is just generic then you can ignore/dismiss it.
