To launch a feedback survey, you must create a new event, as yve supports only one questionnaire per event. In this feedback event, you delete the question regarding participation and add your feedback questions.
You can set up radio button questions using the "Radio Button Table Row" display format and assign a numerical value to each option (e.g., 1–6) for analysis purposes.
You can assign an ID to all confirmed participants from the completed event via "Participants > Assign label" and then use this label to assign them to the "feedback event."
You can then display the results as an average value using the "Summary Chart" option.