The fact is that you do not even need to click on it in the control panel in order to use it.
The script is already stored on the system and added as an alias to apache. This means that it is accessible from http://www.your_domain.com/cgi-sys/FormMail.cgi (watch out for those caps) (and your_domain.com may be either your own or any of your hosted domains)
Beyond this point, all you need to do is write a form that submits the information to the URL above...\'
Here is a sample Form that you can submit to all your clients...Just remember to edit the (values) to your own