Thanks for the comments.

In most cases KDE is loaded it brings it's own set of configs & settings. Once KDE is fully loaded, the /home/knoppix/Desktop/KNOPPIX.desktop
file is run. It opens up Konqueror and displays the /cdrom/index.html

But I want to run my Custom Application (for example a PC utility, like some Partition utility) after KDE load.
For example DSL (Damn Small Linux) has made their desktop.

I don't want to run any desktop, but only my utility program after boot the PC.

Actually I am developing a PC utility (Disk Eraser) for my own interest. And I need to run this utility at the very first time,
because I need to access the System disk.

I want to use KNOPPIX because It has all the configuration already.
And I can't manually create such liveCD with only by myself.
I have tried many months, but failed.

I think now you understand my point.