iCloud photos no longer showing as Apple TV screen saver

My Apple TV used to show my iCloud photos that I had uploaded through iPhoto. Now when I try to select those photos as the Apple TV screen saver, I get a message saying:

"Unable to sign in, iCloud is not currently available. Try again later. For more information, go to http://www.apple.com/support/icloud"

The only thing to click is "OK".

I've gone to that website (no help).

When I sign into iCloud on my laptop, I can no longer see my uploaded iPhotos in the cloud.

1. Does this have something to do with iPhoto now becoming 'Photos'??

2. Why can't I sign into iCloud on my Apple TV. I can sign into my iCloud on everything other device I have (Laptop, iPhone, etc.)

Thanks.

Jeff