The two people on FiLife who know the most about how FICO scores are calculated are:

Dean Binder http://www.filife.com/user/Dean
&
Dave Hanson http://www.filife.com/user/Dave+Hanson

Either one of these guys will be able to answer any question you have.

Paul is kind, but sadly, the FICO score forumulae are closely guarded secrets. In fact, Fair Issac's position is that they are "trade secrets", and the regulators and court system have not disputed this position. As long as these officials support this position, we won't have detailed information on the secret formula any particular scorer uses.