Simple question : when i make a backup using Sysex dump, can i record Project , Pattern and Sounds in a single .syx file ? Or do i need to record separate files for each category ? 
Nobody ? 
As you know from page 16 of the manual, a Digitone Project includes all 128 patterns and the 128 sounds in the Sound Pool.
So if you save the Project, you also save the current patterns and the contents of the Sound Pool, as is written on page 66 of the manual.