I finally got it right to make my *own* custom installation with custom configuration files,
First I had to install Linux and VirtualBox, got the latest versions, I used Ubuntu 10.10 and had to install many
additional packages using the command apt-get install "xyz".
(1) I downloaded the trunk from svn, using the svn command : "svn co svn://svn.openwrt.org/openwrt/"
(2) Ran "make menuconfig" selected my Router as well as to build the ImageBuilder,
(3) run "make" : This takes quite a bit of time on a virtual machine.... WARNING!! be prepared to wait a long time
after everything is built,
(4) Locate the ImageBuilder in the bin folder (/openwrt_svn/openwrt/trunk/bin/ar71xx)
tar -xvjf OpenWrt-ImageBuilder-ar71xx-for-Linux-i686.tar.bz2
(5) Then follow the steps as documented here (http://wiki.openwrt.org/doc/howto/obtai … e.generate)
Hope this helps someone out there, good luck :-)