Yesterday I downloaded Cartagra «Rebirth FHD Size Edition» (Innocent Grey / Gungnir), mostly because of the remastered character sprites and backgrounds, but I've come across a wall at the moment of extracting them. Unlike previous games, this one has the images in a .cz file format, and so I can't view them or convert them to PNG. I've noticed that GarBro is able to view some of these .cz files, so I did some digging and it seems it's because of this:
The files with CZ1 work fine.
The ones I'm interested in have this and GarBro can't view them.
If I manually change it to CZ0, CZ1 or CZ3, it does "work" and GarBro can view them, but the image ends up being really, really distorted.
I'm not sure if this is some kind of compression or encryption thing, but this is where I'm at right now, so any help would be highly appreciated. I'm not sure where to go from here, I just want to be able to convert them to PNG, at least.
If there are any tools or scripts that may be able to help, please let me know!