I don’t know why, I thought I HAD to push the “digipro” button in C6.
But I manage to load the sysex files directly into the digipro manager (thx PeterHanes)
I still have to figure out why the waveform are put on awkward positions, but I guess it’s something within the sysex.

I have very quickly looked into this sysex stuff to see how I could mess things up. I found some hexadecimal code and it reminded me how assembly could give me some spots ^^
So I fled like a coward…

edit : ORG was the parameter to avoid to specify the position I wanted. Get it.
Now I still have to try to create some chords waveform from what I understood from your explanations, @Veets
It seems I have to tackle the fact that the 5th waveform will not be at zero when the waveform ends.
Now I guess one can double the waveform to get it, but I have to see if this works.