Hi Don! Good question. We actually just updated the docs to make this more clear, but they won’t be deployed until the next minor release. Currently, custom actions that are triggered via mapping do not return UserUtteranceReverted(), so you’ll have to add that to your action. In addition, at the moment, if you want a maping to a bot utterance (utter_) to be reverted, you’ll have to write a little custom action to do it. In the future this will be easier to configure.
More info here: How to create a partially rule-based conversation within a chat dialogue