A commentary on Ecclesiastes attributed to Salonius of Geneva does exist in English, I find. This Google Books page tell us that a certain William Pollard in 1615 produced a translation under the title, A misticall exposition of doctor Salonius, borne at Vienna and bishopp of Fraunce, upon the Ecclesiastes of Salomon, in manner of a dialogue. The book is 182 pages, although probably small ones. But the book itself is not at the link.
Does anyone have a copy? It must exist in one of the repositories of early English books, I would have thought.
The Latin text of the commentary itself, according to this link, is to be found in PL 53, col. 967-1012. A quotation suggests the interlocutors in the dialogue are Salonius himself and his younger brother Veranus. Veranus mentions that “there is a time to laugh and a time to weep”, and Salonius suggests that, far from describing our present life, it means that we weep now but will laugh and rejoice in the new Jerusalem.
But I believe that the commentary is spurious, and not in fact by Salonius himself. The same text is also transmitted under the name of Honorius of Autun (PL 172, 311-348).
UPDATE: The Latin text is here in the PL 53 volume.