Few questions about NAME.postinst and custom packages.

["Branimir Karajcic" <branimir.karajcic@gmail.com>]

Hi, 
I am making custom distribution for my company which is using some VOIP software that is not really well supported via aptitude. For some applications I have created debian packages, for others I couldn't (example Zaptel)

Maybe this questions are too basic, but I couldn't find detailed Simple-CCD documentation:

1. Can I use NAME.postinst to work in /root directory with first command being "cd /root"? I wonder how can I get extra files onto ISO, so I can copy the file/files to  /root folder.  Basically what I want to do is to get 3 tar.gz files to /root directory and run the installation of these programs from source with a bash script. Or is the NAME.postinst only there post-configuration.