I have no any idea about how to generate an iso from it.
As for Debian Pure Blend, I'm reading http://blends.debian.org/blends/ now. My plan is to create and customize the skolelinux / debian-edu iso first, then study how to merge into the debian edu blends.
We hope to create a useful demo iso before the end of March. Could anyone please give me some hints about how to do it?