New 2004 745i owner

Hi, I'm new to BMW community. I recently purchased a used 2004 745i from dealer. Vehicle has some small bumps and scrapes, (what a shame!). Electrically and mechanically everything is working. System tests OK! Car has 121K miles, rides smooth. Had to add some Hydraulic fluid (CHF or CFH) and some washer fluid. New tires, Does not have V60 phone, but found the BTUM and successfully linked to my Samsung Galaxy S2. Able to use voice commands for Nav, ENT, Telephone....Noticed some fluid leaking from left front tire area, I need to investigate. Navi 02 version 4.4.2. Now looking for a CD changer cartridge, discovered mine missing. Hope is was a cartridge issue and not a changer issue.