[stope4]

did you press the button on the front of the proportion valve. Usually you have to depress it to get the valve equalized on the inside. If it were me, I'd find a used one and repalce the rubber gasket on that fitting that's leaking. You can then clean the whole thing out and experiment with how the valve works on the inside. Their not that complicated and you can replace the o'rings at the same time. Just make sure you get o'rings for brake fluid service.