Except the 'WonderBoy in MonsterLand picture', the colors on others games seems to be inverted?!
Maybe you're inverting some colors? Try to swaps the three color wires? (I mean maybe you're sending the blue signal from the board into the green input of the TV for example...)
I've also have similar thing... the 'Brightness?' potentiometer (one of the two pot close to the high voltage, usually in black) was too high, and in some part of the screen, some areas were 'color saturate'...