We have a required questionnaire that is required a time of checkout. 
Has anyone been able to integrate a formidable form to Woo checkout page? I am sure I can use a shortcode to include the form on the checkout page, but how do I capture the data?
Here are the options I could see;

1. [a] Capture form entry ID and link it to the Woo order. [b] Integrate a Formidable view to the woo order record, which is linked by form entry ID
2. capture form data and include in Woo order as custom fields
3. add a form page between the cart and checkout
4. create a form popup on the checkout page

 
Any insight would be appreciated. thanks