Hi Hillary,
please find the resolution steps for unlocking the rule.
1. Go to sql server mgmnt studio , open default information steward installation repository. is repo (DB_IS), take back up of table dbo.mmt_rule
2. edit mmt_rule table by executing the below command
update dbo.mmt_rule set state = 'A' where is_current_version = 'Y';
now try to import. Importing will be successful
Note: after executing above command rule status will be changed from editing status to approved status
regards
krishna mohan