I assume you have bled it with the peddle down as it says in the instruction, if so i would try it without depressing the brake peddle, see if that helps at all. When mine didn't bleed i took it too my mates garage as it was going in for MOT and they did it when i aske how the did it they said the normal down, up, down, up way.
Also did you have the wheels on the ground as i think this affect it because of the load sensor.
Hope some of this helps.
Lee.