Dear Wolfgang,

Thanks a lot ! In order to verify the mechanism with a French document, I have set your code sample with French commands and replace 'Content' by 2 texts of around 15 lines each (after removing \input tufte and \input ward previously given), and fill the tables titles with words of my own. All is fine, except hyphenation which doesn't appear here.

\mainlanguage[fr]

\setcharacterspacing[frenchpunctuation]

\defineparagraphs[n=1, align={hz,hanging}]

\setupalign[hyphenated]

You may try with this text (in place of 'Content') :
« Dans la société présente, où le jeu de la spécialisation s’est outré automatiquement, les fonctions intellectuelles et les fonctions manuelles ne sont presque jamais attribuées aux mêmes ouvriers. »