Can't download Photos from iCloud library to Mac
I generally take photos on my iPhone 6 and want to to view them on my other devices including iPAD and Macbook Pro. I think this is what iCloud library is intended to do. I have successfully uploaded all photos from the iPhone to iCloud Library and subsequently downloaded these onto the iPAD, just by setting up iCloud Library and Photos correctly. However, the same photos are not always downloading onto the Mac. I have a Macbook Pro running Yosemite 10.10.5. and running Photos Version 1.0.1 (215.65.0). When I take a small number of photos the syncing works fine and photos are present on all 3 devices. However, if I go on holiday and take, say 500 photos, with iCloud switched off, when I switch it on it works OK to upload to iCloud and download to the iPAD, but not to the Mac. On the Mac it will starting preparing the upload and downloading but then iCloud Library Selection in Photos>Preferences>iCloud will uncheck itself and the upload/downloading stops. I have tried this many times. I have also checked that the Systems Preferences>iCloud>Photos is checked. Again, this sometimes goes from being checked (tick) to a - sign. I have 50GB capacity in my iCloud account and only use less than 20% of this.
MacBook Pro with Retina display, OS X Yosemite (10.10.5), Photos Version 1.0.1 (215.65.0)