How I could have benefits if I build my FairWind system?
You are in the FairWind manual example case: the maxi displays could be connected directly to FairWind and the transducers too. The echo sounder should have a NMEA output compatible with a RS232 serial port. You could connect it using a serial/usb adapter or directly on the FairWind board. Maybe a good quality marine GPS receiver with usb plug could be connected to FairWind in the way that could act as position source for the anchor alarm.