I have a one drive folder in File Explorer but none of my files are there. This despite all my photos showing in the photos app. Did not have this issue on My surface 2 with 8.1
It doesn't sort by folders though, so you'll have to scroll to the date the picture was taken, witch really sucks if your a digital artist. I wish the app would show the folders, like it did in windows 8. I don't understand why they would remove a nice feature like that.
Stumbled across it on my YouTube subscriptions. Basically you set it up a as a network drive using your one drive credentials. Works a treat. https://www.youtube.com/watch?v=qm1Of4eFDDY