I had the same problem as BusinessNaples described in this ticket - https://formidablepro.com/help-desk/required-fields-suppression-for-admin/

With some help, I created some code that solves the problems. I want to post it here for anyone else who needs it. Now, Admins can edit forms in backend, while restricting certain fields on frontend.

This can come in handy in a few different cases. First, when using the API, you can accept a file url, and import it onto your site. Second, if you would like to accept links to files that are already online, rather then requiring users to download and then upload an image.

This example uses two different fields: one for the file url, and one for the upload field. The value in the url field will be used to fill the upload field when possible.

This code will get the value from one field and copy it over to a second field.