The HoloLens emulator is a handy tool for quickly checking out code destined for the HoloLens itself. Apart from requiring Windows Pro for Hyper-V support, the only problem encountered was to give the HoloLens emulator access to some sort of network. I basically followed the instructions here but still encountered issues with getting it to connect to the sharing server, probably because I wasn’t thinking about what was happening.
The HoloLens emulator automatically creates the Emulator NAT Network Adaptor and Emulator Internal Adaptor when it starts up if they aren’t already there. When you manually create the new switch and add it to the Emulator NAT Network Adaptor, this couples things to the physical network adaptor. That adaptor will get an address on the external network (e.g. 192.168.1.23). However, the emulator is connected internally and (in my case at least), gets an address of 172.16.80.2 while the host PC gets an address of 172.16.80.1 on that interface.
So, if you run the sharing server on the host PC, the emulator needs to be pointed to the server at 172.16.80.1 rather than the 192.168.1.23 address that a real HoloLens would have to use. Once I realized that, things started working.
Another problem with my initial configuration I suspect was that the host PC originally had a static IP address. This seemed to cause strange effects and changing to dynamic IP let things work properly.