(DG) Smart controller x5 nmea

I have a smart controller X5 and nmea mux for multiple devices. I did have a c80. The c80 had a direct nmea connection that worked along with seatalk connection back to smart controller. I would like to replace my c80 that bit the dust with a b&g zeus. The issue I am having is I am sending all the nmea to the smart controller but it is not bridging it and sending it back out on the seatalk ng connection that goes to the ST70. I did set it to 4800 baud. Any ideas?

Thanks Deb