To make field not requried you need to
1. back up the /include/class.ticket.php file.
2. Edit /include/class.ticket.php
A. circa lines 1592 - 1602 inside function update()
locate the variable you want to make not required and change 'required'=>1 to 0.
B. circa lines 1854 - 1877 inside fucntion create()
locate the variable you want to make not required and change 'required'=>1 to 0.
example:
$fields = array('type'=>'phone', 'required'=>1, 'error'=>'Valid phone # required');
would become:
$fields = array('type'=>'phone', 'required'=>0, 'error'=>'Valid phone # required');