A very strange phenomenon. 

I reformatted my disc and reinstalled Yosemite and rather than copy from my CCC clone - or Time Machine backup - I thought I’d do a “virgin” install and downloaded Aperture from the Mac App Store. 

However - despite my the shared photo streams on iCloud working perfectly on my iPhone, iPad, and iMac - the ones on this Macbook are mostly empty.

I have tried “resting” the iCloud photos by removing the photos and restarting and then re-choosing it - several time. But nothing changes. 

Is there a way I can force it to sync my streams?

Thanks in advance.