Hi Giorgio, first of all I want to congratulate you on your program, Peazip is an excellent program, the idea of agglomerating many compression formats in a single GUI is formidable. On the other hand I tell you that ZpaqFranz is a program that was based on Zpaq and continued its development, giving it more importance as Backup software, so to use it like the old Zpaq, you have to use the parameter "-715". I want to make you ask for two things, the first is that you enable the compression levels...
Zpaq was discontinued a long time ago. Now support zpaqfranz