osTicket + .NET + payu + own web site integration development

We need to integrate a job order activity in our website with osTicket. Each job ordered by a user has to be created as an osTicket. This jobs have particular data as userid,user name,recordid, recordname and other fields. Each field has to be shown in the tickets administration site. Also each user can access to their ordered jobs (tickets) within their own accounts in our web site with the status of the ticket. The user also has to have the ability to cancel the job in certain stages. The site is developed in .net. and osTicket has to be customized.