-Is there a way to change the configuration of a REST Connector after creation:

• yes, we could change the configuration after creating the assets via Rest Connector wizard but it will be a manual step on analysis & need

-Change the JSON of a request/response?

• yes, we can update the JSON request & response property mapping at data transform rule created by rest wizard

-Add another method and have its rule generated?

• could you provide some details on add another method means...? are you referring to GET, POST, PUT like methods... these could either be created manually or via rest connector wizard.

-Delete all the records generated for a connector? (like the "undo generation" option right after the creation of a connector)

• we could bulk delete all the rules generated by rest connector wizard
  • if the rule generation page is still open and accessible
• ideally the connector rules are saved in a separate ruleset. so deleting the ruleset via Delete a ruleset wizard should help (DesignerStudio --> System --> Refactor)
• if the rules are created in a same ruleset but a different ruleset version, we could still delete the version using the same wizard 'Delete a ruleset'
• otherwise, we need run a report definition on Data-Rule-Summary class to know the latest rule updates by the current operator and delete the rules manually.

Please note: Rest connector wizard is accessible via DesignerStudio --> Integration --> Connectors --> Create Rest Integration from Pega 7 series...