So it's starting to be a bit off the conversation, but...
If you rather, i can create a new post instead.
So here is the next question :
As i can't add metadata to cbz, i've search for another way to read at my comics on kobo glo. I've found out that the only other format that doesn't show the bottom information bar on kobo is the mobi.
So i convert my cbz to mobi, and it looks great, except for the cover. I tryed differnt solutions, but it looks like the cover is a random page, not the 00 or the first one, or the one i ask in the metadata calibre field.