After doing some more testing on the 8.1 photos app I`ve discovered the following
All my photos which are stored on a Server 2012 Essentials network share (which is included in the pictures library) mostly will not show up in the photo`s app - with the following exceptions
- Most of the time, the live tile displays pictures from a network share
- The lock screen slideshow will also show pictures from a network share but seems to max out the CPU (on a core i-5)
- The folders for my (network stored) pictures have shown up in the app maybe 3 or 4 times since installation, but as soon as you try and navigate into a folder to view pictures, the app crashes.
If it were not for the frankly baffling response given by an alleged microsoft program manager earlier in this thread, I`d suggest that the app is simply not feature complete.

