Access in what sense? You can edit/create rules with PaperUI, but its not really developed. You can edit/create rules in a JSON file, and import them from karaf console - as illustrated a few posts back.
Once a rule exists, it gets triggered to run by system events, such as an Item update. If you wanted to ‘access’ in the sense of making the rule run, you’d need to cause the trigger i.e. update an Item.
NGRE is like most experimental things poorly documented. @rlkoshak is working on it.
