Thanks to all.
I have tried the suggestions. Unfortunately with no results. I am not a computer freak nor expert. I only want to service Wikitree to the best of my abilities.
As to my original problem: I still remembered the adoption dates and could find them on that basis in the watchlist.
It raises a more fundamental question: as the number of records keep mounting, integrety and maintenance will become an issue, especially for the generations after us. Is there a policy to develop tools and/or algorithms to guarantee this?
Peter