conditional logic wipes out the form

Using GF on wordpress 2.9.2 and Headway theme 1.6.3.
Have a simple contact form at http://www.heskethmediation.com/contact.
I wanted to ask if users wanted to be contacted by email or phone. If email the email field appears. However whenever I add a field using conditional logic the form does not display and I can not open the visual editor in Headway even in safe mode.
Anybody know what the problem is?
Thanks

Hi Kevin,
this is the footer.php file:-

<?php headway_footer(); ?>

<?php headway_html_close() ?>

So it's not using the function, how should I amend the file and will that affect the rest of the headway theme?

- on further investigation I don't think this is the problem. I was trying it out on another site and it has the same footer.php file and I wasn't getting the problem. I have discovered that the problem only arises when I use the Headway Gravity Forms leaf so I will let Grant know.

Thanks