Worked immediately, no need for tweaks, with the exception of WiFi. My access point is using WPA2 with AES (no TKIP). I manually configured the wpa-supplicant stuff and had no further problems.

I'm using the HiFimeDIY Sabre USB DAC and a generic USB WiFi adapter. Both were purchase from eBay ($55 for the DAC and $9 for the WiFi stick).

The audio sounds great – no clicks/pops. The GUI is easy to use. I've added a DLNA renderer (as per instructions on this forum).
Advice to all having reliability problems – plug your USB devices into a powered hub – not directly into the pi.

Suggestion for improvement – limit access to settings pages & provide administrator controls to blacklist abhorrent spouses/kids/guests (you can never have too much control).

To the development team – fantastic, valuable work. You've done something that is making lots of people happy.