Don't worry, I am not insulted. Although a computer programmer by trade, when it comes to NMEA network installations I am a neophyte
To answer your questions, yes, all connections are as in the diagram I included in the first post. In detail:
Backbone: female terminator - T -T - T - male terminator.
Drop cables: GMI 10 - Power - Triducer to each respective T middle connector
GPS 19X cable connected to the respective cable that ends at the Power/NMEA0183 connector at the back of GMI 10 and both GMI 10 and GPS 19X get power from direct wire connections to a switch on the 12V electrical panel and NOT from the NMEA2000 bus.
GMI 10 is a headless MFD, it just displays information from external sensors, it is not a chartplotter or GPS receiver itself.