I did it with my BD5a, I routed boost pressure from the single turbo through the 'exhaust gas supply control valve' solenoid before entering the 'secondary side' of the differential pressure sensor. If you understand how the twin turbo system works it makes sense.
I'm pretty sure the BH & BE have the same BBoD and diff pressure sensor (correct me if I'm wrong) so it should work the same.
I still use the same ECU, just with a single turbo setup, and it runs fine with no CELs, has done for about two years!