hey bigcheese.
I was lucky enough to win one of these scholarships back in 2004. Sure there are people with more recent experiences but from what I can remember we had an overnight stay in Cranwell, getting up very early to do some appitude tests. These were on a computer with a joystick and rudder pedals but I can't for the life of me remember what you had to do.
After this there was a lot of waiting around until your interview, and the guys who were going for RAF selection were also there waiting in the same room. I waited from very early in the morning until about 4pm. The interview wasn't too bad though (the waiting was worse!), the guys were pretty friendly, asked me about some past experiences and I think they mentioned CTC too. I was a bit concerned as most of the other applicants were Air Cadets (i've never been one) but my worries were unfounded. They just want to get to know about you, and your passion for flying really.
Sorry I can't be more help.
GOOD LUCK with it!