Has anyone succeeded in working with response_variables?

No, this 100% works if you keep it within the proper scope. I’m using it. Whatever you’re doing is not correct. Here’s a full example:

  - variables:
      calendar: calendar.xxx
  - service: calendar.get_events
    data:
      start_date_time: "{{ today_at() }}"
      end_date_time: "{{ today_at().replace(year=now().year + 2, day=1, month=1) }}"
    target:
      entity_id: "{{ calendar }}"
    response_variable: raw_events
  - variables:
      gathered: >
        {{ {'events': raw_events[calendar].events} }}

So please post your code. I’ll help you fix it.

EDIT: If you’re referring to this post:

If statements are a nested items. It won’t work with if statements, hence why you have to do…