on the summary page, go to the bindings panel, click the plus button and select Form Data
on the Form Data dialog box, click the folder Icon and select the initial form page. This will add Dynamic data bindings for the form on the preview page, use these bindings to layout the Preview.
Now, you will need to create 2 form on the preview page, each with hidden form elements that are named the same as the form elements from the initial form page.
The first one will be the Insert form, leave the forms action blank so it will post to itself.
the second one will be the Go back and make changes form, set the forms action to post to the initial form page.
On both forms, select the each hidden form element and click the lightning bolt icon next to the initial value option in the property inspector, and select the corresponding form element from the bindings panel.
do the same on the initial form page, bind each form element to the corresponding binding in the bindings panel, this is done so that when the make changes form from the preview page posts back, it will remember the info that was initially posted.
Now on the preview page, you can add the insert record behavior, make sure to set the trigger to Current Page Submit.