Make sure first to download these pages:
You can edit the subject by double-clicking the email in the Server Behaviors window.
If you want to update the subject line in the code directly you can edit line 10 of: /webassist/email/waue_Contact_2.php
To remove unwanted fields you can edit the page: /webassist/email/templates/Blank5.php
The form fields are dynamically added, but can be removed on the top of the page. I've added code already on lines 16-17 to remove the hidden field and submit button.