Customize fields on the Submission gathered page?

Is there a way to include an additional field from the form on the submission form that the creator sees?

I'm looking to include the Terms & Conditions that are signed for as the form is completed.

Yes that's possible. Simply edit your form and add the terms and conditions field there. After that, hide that field (right click > hide field) so it will not be available on the live form. 

Now, when you go to your form submissions page and edit a submission, you should see the hidden field you've added on your form. Hidden field values can only be edited by you on your form submissions page.

Hope this helps!

The only way I can get the terms and conditions to appear is to select the "show the headers and text" option, but then that shows all my pictures and descriptions along with it.  Any other ideas?

This option "show the headers and text" are for text and images on your forms only. So you mean to say you have added the terms using the text tool? This shouldn't be the case when you use the terms and conditions widget like this http://widgets.jotform.com/widget/short_scrollable_terms which I can see with your form here http://www.jotform.us/form/52168012111136. I assume that this widget fits in your requirements? If not, let us know so we can assist you further.

Thanks!