Hi.
Curation Complete !!
The problem, as earlier suggested, were corrupted photos in the library that the curation process could not read.
As above written, I have search for Photos that hat no ISO or Camera Model Info in the Metadata. I have found a few, but the ``Analysing... ``was still going. My Library has around 82.000 Photos and Videos.
Adding the Permissions to ``Administrators`` and ``Apply to enclosed items...`` + a restart, did not do anything. ``Analysing,..``was still going.
Today I have decided to take one by one the Photos in the Library (All Photos - view) and to my surprise I have still found a few. All of them were taken in 2014-2015. Back then I had my old iPhone 5s. After deleting these, the Curation was in a few minutes complete.
Needless to say that my iMac, late 2013, was always on since mid of November..., hoping that it would finish by itself... no it doesn't.
For those that have tried everything and the process is still not finished, my suggestion is that you should search manually for the corrupted Photos.
Thanks to everyone that wrote here trying to help us!