pagebreak for non-members

I think I would create two forms. Create your first form without page breaks, then duplicate the form, and add the page breaks. Embed the first form in a page and make it so only registered and logged in users see that form. In the alternate content for the form, the message that non-logged in users see, insert the shortcode to the form with page breaks. Would that work?

PHP will not be processed in the content template or form. However, shortcodes are processed in both places. Maybe you could write your function and convert it to a shortcode, then use that shortcode to break the page for non-members.

If your function is written to do that, then yes. I am just saying you can't use PHP in the content template or in the form. But you can use a shortcode. If the shortcode executes the proper PHP or JavaScript, then yes, it would work.

I wonder if you could add a section break and add the conditional logic to it, and set it to a condition which would never be true. That way, the section would always be hidden. Then you could write your function such that if the visitor is logged in, you run jQuery to show the section.