Broadband is incompatable with a few additional services you can purchace from BT. If your phone line has some of these services enabled, then broadband will not work. When you use the Freeserve site to check for broadband availability, it will tell you if you have any of these incompatable services. The tiscali/BT etc. checkers do not. If Freeserve detects that you have incompatable services, it will not let you order broadband - you can contact BT by dialling 150 to find out what incompatable services you have on your phone line and to get them removed. You should then be able to order BB.
As for me, I am also on Freeserve Anytime, and do not have any problems with connecting, apart from recently when, in the evenings, it can take up to 5 attempts to get on. However this is rare for me and I always get on eventually. I wish I could get BB but I can't, because BT wont enable the exchange (56 people have registered an interest but we still dont have a trigger level)
hope this helps,