CS = 'Coffee Snobs', CS7 = beans roasted to the level of 7 on the coffee snobs membership card (which contains images of beans roasted to different levels (up to 12). These CS levels can be roughly translated to other systems (City, Full City, Vienna etc)
BeanBay = Bean Bay (see tab at top of forum page)....you can see a photo of the coffee snobs member card there too in the 'other stuff'.
FC = first crack (not 'full city' generally)
SC = second crack
and so on.