Shared Photo Stream shows empty folders on one device only (after iPhoto update?)

I have several Shared Photo Streams, until yesterday, all worked flawlessly. As of yesterday all my iOS devices can see the content I posted to iCloud prior to yesterday and new things posted after I noticed the problem. However, my Mac is now showing empty share folders for everything prior to yesterday, iPhoto and Aperture show a cloud icon with the folder name and who it's shared with, reports 0 images. New photo's I've posted from my Mac today show up on all devices.

I recently ran the updates for iPhoto and Aperture, when I launched Aperture it coughed up many errors that my library needed to be rebuilt and asked me to locate a bunch of individual images, but nowhere near as many images as I had in Shared Photo Streams...

It seems that something has erased my local copy of the Photo Stream images from my mac. Any idea if I can force the mac to sync them back from iCloud?

I'd rather not delete the folders from the cloud because 1) It took a while to get these albums together and posted 2) I'll likely loose the Comments added to the images.

Any help would be appreciated.