I am aware of these documents: https://help.ubuntu.com/community/InstallCDCustomization http://blog.self.li/post/74294988486/creating-a-post-installation-script-for-ubuntu on making custom Ubuntu installation CD or DVD media. It's particularly clear on adding custom packages to the install.
But how can I customize user preferences, such as sleep timing or package update policy? I'd like to do this either as a custom installation CD, or at least as a click to execute script. The goal is to set up a bunch of machines, all with the same preferences settings.