pugwash4x4
I did stage 2 last month and can confirm that i didnt have an interview and there really isnt anything you can do for the computer tests. I know its hard not being able to prepare. Just get there in plenty of time to relax and get a good nights sleep. There are some cubes thrown in and most of it is on reactions and dealing with pressure and its very fast paced.
Best thing i can suggest is to relax and enjoy the day.