Do customers need to be registered to submit tickets in the Help Desk Ultimate extension?
The Help Desk Ultimate extension can handle both guests and registered customers.
Your registered customers can create new tickets and manage their existent ones from a special tab in their account dashboard.
To allow posting tickets to your guest users, enable the Contact Form option on the Help Desk-> Settings-> Modules Integration backend page.
If the Contact Form integration is enabled, all the messages sent via the native contact form are parsed to the Help Desk tickets.