The UPnp/DLNA client seems to be broken for Pictures. I have tried 2 servers, Plex and JRiver MC with the same results. The problem is at some random point it fails to navigate down into “subfolders” and just keeps presenting the same folder that you select so you can never get to the pictures. For example, I select my Plex server, then select Photos, My Photos Library, By Year, 2015. When I select 2015 it just keeps displaying the 2015 folder. It seems to happen randomly and not at the same folder level every time.
Note that this doesn’t seem to happen in the Kodi DLNA client when browsing the same servers for videos (just pictures). Also note that I am able to browse pictures fine for these same servers with different DLNA clients other than Kodi.