multiplayer.ini you need to edit in ZH in generals it was gamedata
the cash you specifie in gamedata.ini also need's to exist in multiplayer.ini
and for the GC it is specified in the .map for that spcified general so you gotta edit the GC maps to alter the starting cash.
You must edit every GC map for zero hour to do that you must open World Builder and look at the scripts. Scripts->The player->Give Player money EASY, MEDIUM,HARD and edit this Set Player 'ThePlayer''s money to $ 6000000 or ...