I was browsing the disassembled K2 Java code and noticed that the K2 supports direct viewing of cbz files (zip files filled with images). The .zip or .cbz archives can be dropped directly into the pictures directory and will show up (without having to Alt-Z) in your home menu, and open in the picture viewer.
Unfortunately, the K2 picture viewer is still buggy and seems to still crash on larger images, so pre-processing with Mangle or something similar is still preferred.
Also, the K1 (as of version 1.2) doesn't seem to implement this.
