1) Is it possible to modify / add any needed custom fields for a ticket? if so, is there a limit to the number of fields that can be placed on the submit ticket page?
=> You can add any number of custom fields you want to submit tickets page, there is no limitation. However, after customer enter data for these custom fields, you can only view the value of these custom fields when you view the ticket. You cannot edit the data of these custom fields in the current version.
2) when a user submits a ticket, will he recieve an Email confirming that his ticket was submitted? if so, can I edit the content of that mail as I wish and include in it the values of the fields that the user filled in when he submitted the ticket?
=> Yes, he will receive the email (and admin will receive notification email as well). The content of the emails messages can be configurable in Configuration function of the extension
is there a page that shows a summary of all tickets a specific user had sent where he can review the status of each ticket? if so, what are my editing possibilities for that page? can I add a file to be downloaded directly from that page?
=> Yes, that page is called Ticket History. You can add file to a support ticket and users will be able to download it when viewing the ticket.
Hope my answers are clear to you.
Regards,
Tuan
