Hi Ronald,
When I use a rollback in a submicroflow does it revert only the changed data of that object in that submicroflow?
It will revert any changes made to the object since last commit, including changes in other parent or sub microflows. I have updated the documentation accordingly.
It would rollback every change on that object since it's last commit. Even in parent microflows. Also if you change an object in a submicroflow that object would also be different in the parent microflow activities after the submicroflow call.