In short:

GA is the ultimate power, as long as it is legal, following the bylaws and has funding (for cases needed).
Board can throw over or return to discussion with GA when things seem off, legally or missing funding or not in line with the bylaws.
Board can act on their own and as long as GA agrees proceed, GA can block board decisions and revert them.
Council has no powers but those explicitly handed to it (that is more responsibilities than real power) and a voice in discussions.

Maemo Community is all of us - in general referred to as garage accounts - they vote for Council

GA is the (in our case) annual meeting of all members of the MCeV

MCeV is a registered at court entity representing Maemo and its community (when HiFo finally disappears). It consists of a Board voted by the GA and a Council voted by the maemo community (garage.mo) and of course of the members and founders of the MCeV itself.

So separation is [MCeV(Board,Council,GA,Members)] != [Maemo Community(garage,Council)] while they share the same council. Garage accounts are mentioned in the bylaws as party to elect the council.