Hi again!
Apparently I have to “Renew support to get help from Kriesi for 6 months” (which costs $ 49,00) to get an answer here. Wow… okay… I understood.
Indeed, the failed update to 3.8.5. managed to delete completely the folder “Enfold” on my server, so I had to reinstall the whole theme by FTP following the instructions via https://vimeo.com/67209750. After that, I activated my (preconfigured) Enfold Child theme and… it works now.
Gramsch