Got to the 'Fields' tab on your custom report and click on the advanced field settings for TicketNumber.
After you clicked on this icon you will see following popup windows:
If you want to use the field value in url you can fill the "Url" field (#1).
For example - "home/ticket/viewticket.aspx?id={0}". In this case "{0}" will be replaced with field value.
On view ticket page we are using "ticket id", not "ticket number", in this case you need to add this field to your report and use it in "Url" filed.
For example:
TicketNumber field has following value in "Url" field: /home/ticket/viewticket.aspx?id={2}
{2} - is the number of TicketId field in report and this field is hidden.
In this case you will see following links
