You can see on the attached image, that after Auto Routing, I was slightly confused as to why there was still an airwire indicated by my white/gray arrow - as it looked like everything was connected, including the thick yellow net for 3v3 net. What had actually happened is that the router had created a net wire correctly, but routed it to the EDGE of the bottom horizontal yellow trace - where my other arrow is pointing. Clearly, this meant that the wires were not connected.
I've added support to the project and I will leave it in the current state where you will see this error.