If there are missing rules in the database for a ruleset it just uses the default value from the source.. which you may or may not like.
You can easily copy your entire ruleset into a new ruleset with SQL
Code:
INSERT INTO `rule_values` (`ruleset_id`, `rule_name`, `rule_value`, `notes`) select 55, rule_name, rule_value, notes FROM rule_values WHERE ruleset_id = 1
Note.. 55 would be the new ruleset_id and it is copying from ruleset_id 1

(change the values to whatever you want to copy from and copy to)
You may need to insert a ruleset into the "rule_sets" table .. but I have no idea .. but better off doing it
Would be something like...... 55, "PVP Rules"