Hi All,
All problems are solved!
1) I renamed apeisa-Thumbnails-aa083a6 to aaapeisa-Thumbnails-aa083a6 .
2) Then I reinstalled FieldtypeCropImage directly. Immediatly all problems were solved with the website version ProcessWire 2.6.1.
Again, thank you all for your help with my first attempt to move a live website from a terrible hostingprovider (hostinger.co.uk) with redirects to a temporary one (www.kusttram.com/kfc) so that the website can stay alive while awaiting its proper domain.
Kind regards,
Bernard