I would have to agree with ghurd.
Your diagram is not using the alternator as a ground..
If i have this correct , you should connect the case of the alt , to the battery negative .
then connect the B+ to the battery positive.
Your sense wire , ahem, is then connected to the battery Positive.
Since i don't have a schematic of the alternator , i have no clue what the green wire , is for .
ditto on the brown wire .
I did some searching on the net and discovered that the slightest drop in voltage , as might be caused by switching on a light bulb , actually turns on the regulator .
So i would try just connecting the case and battery negative, B+ and the sense wire to battery positive , start pedaling and connect a light bulb across the battery .
Happy pedaling.