LEED Campus Certification with complex buildings conditions

Hi Everyone!....just joining the LEED forum family. I am evaluating a case for LEED Campus Cert. in order to prepare a service proposal, but complex conditions are encountered in the site. I just read the MPR and the 2010 AGMBC, and while reading previous comments on this website related to the subject, some things are clear, but some are more confusing. Questions: 1- Whether the pre-approved Master Site credits are to be applied to each individual LEED project certification, when applicable to one or more projects, or these credits are consumed when applied to the first LEED project certification? 2- A very particular condition in the site is as follow: Building A (BA) is a 7 story existing tower (only 1st and 3rd floor are owned ), Building C (BC) is a 4 story existing building in operation. As an in-fill building, a third will be inserted occupying the opened space separating BA and BC, named Building B (BB), a three story new construction building, intended for leed certification. BB is attached to both BA and BC, and will be connected to both in the 1st and 3rd floor with BA and connected through 1st floor with BC. How should LEED certification process be approached in this case where a new building connects to and facilities are shared with adjacent buildings? At this moment i have considered to use LEED-BD&C. Please correct me if i am wrong. I will greatly appreciate any opinion or suggestion to solve this uncertain case. AM