Adding custom files to Ubuntu CD

Hello to all members,

I was make USB persistent live with Ubuntu 12.04.1. That USB does not run on other computer, I don't know why. Casper-rw file is useful, but I want to include contents of this file into Ubuntu CD (adding custom casper-rw files to filesystem.squashfs or creating a mount point automatically loaded at startup), or load casper-rw file at startup within a DVD.

At this moment I only can load casper-rw contents with CD (reading casper-rw file from HD), USB, or putting all the USB files within HD (Live-HD).

Is not important opening casper-rw file for write mode, only for read. The important question is load contents of casper-rw file or similar included within DVD at Ubuntu startup.

Anyone can help?

Thank you. ;-)