Welcome to Android Central! Go to Settings>Device>Display>Daydream. Assuming it's turned on, which Daydream option is selected? Tap the gear icon next to it, and see if you can select a specific photo album.
That is my question also. I have this black screen with.....no pictures selected.... in the middle of the page. Is that Google wanting photo's or what. Would love to know the answer. Thank you so much. Priscilla Anstey or panstey44