Adam, I reckon it will work mate. To get a router to work on any DSL line, all you need is the login ID and password (usually an email address for login ID) for that ISP. BT ones are usually
firstname.lastname@btinternet.com, with a password of 'BT' (I think this can be any text, as long as its not empty).
So you need to get your Tiscali DSL login details, and enter them in your router setup pages (usually
http://192.168.0.1 or
http://192.168.1.1). You will need to login to your router, and the standard login for that is:
userId: admin
password: admin
It may be different though, do a web search and find the login details for that router if admin and admin don't work.