The best edition, in my view, is the one by Lucile Lawrence. The edition published by the Bohemian publisher does not distinguish between editorial additions and what is in the original. I haven’t seen the Ut Orpheus edition to compare. The ornament you first encounter in the first movement is a turn, which should sound graceful, but not overly slow, as in all notes of equal value. There are also appoggiaturas which will sound like two eighth-notes, only connected very gracefully and expressively.
There may be two sets of “Six Sonatinas” by Dussek, since mine, published in 1956 , in Prague, does not contain the more performed and recorded Sonatina in Cm. However No. 2 in F is included,with helpful added fingerings, and written-out turns. The editor, Marie Zunova, used the original Paris print as a guide and writes on page viii: ‘I leave the music part of the Paris print unchanged. Only a few alterations in the system of writing have been carried out (e.g. transposing some notes played with the left hand from the treble to the bass stave) and fingering, pedal markings, phrasing and dynamic marks, which the original print contains only very seldom, have been added.’.
I appreciate your responses so much! This project has become so much more interesting than it seemed when I began. The more information I find or am given about Dussek, the more interesting he becomes!