I'm using Lightroom CC on Mac OS with roughly 60k pictures and 100+ collections. I can see the collections/photos on iOS and web, just Windows doesn't work at all.
For roughly 2 weeks I'm trying to sync data to my Surface Book with no success.
I updated Lightroom CC on 2/14/2018 and disabled "Graphics Processor" as suggested by Adobe support through Twitter, which stopped the CPU hogging, but still not photos.
Retrieving data ...