I experienced the same problem as Annette. They are all nice and enthusiastic at first. They asked me to pay for a security check which is £44.00 plus an additional £5.50 fee at the post office. You are required to complete lots of forms etc. Since then, I have not received one phone call or email. I rang about 2 weeks after registering to check in for jobs only to be greeted in an unhelpful way. I suggest that you don't waste your time.
It is hard to get an appointment register, but when you do they are very helpful and friendly at first. They get you to pay for CRB and security checks, fill in a mountain of forms (more than any other agency I have been with), sign loads of bits of paper, extra references etc, just to tell you there is no work after all, so here is your P45. My suggestion is just not to waste my time and other people's. If there is no work, don't pretend that there is.