I can�t walk you through every step but here are some tips for survey apps for anonymous users.
Make the survey all in one form without child records. I know that may be different to my earlier suggestion, but I did not realize this would be going to non users..
Have a form to be used for Add, and do not allow editing, only add, for the everyone on the Internet Role.
Have a view form which is just an empty form with a thank you for your survey message.
The firm will need a lot of text instructions so the user knows to answer the questions and then Save the record.
