Modifying the NST ISO Image
If you want to modify NST and you're familiar with Linux, you can modify the toolkit and rebuild an ISO image file on a Linux system. The documentation walks you through the process of rebuilding the package and creating a new ISO image file. If you don't want to rebuild the package, you can use a tool such as WinISO Computing's WinISO (http://www.winiso.com) to extract all the files from the ISO image, modify the ISO contents, then recreate an ISO image file. Make sure that you don't add so much material to the ISO file that it no longer fits on one CD-ROM.
I used WinISO to modifiy NST, and the $30 tool was easy to use and performed well. I simply launched WinISO, opened the image file, and clicked Add to add other programs to the ISO image. Next, I clicked File, Save As to save the ISO image under another filename. I then used CD-ROM burning software to create a bootable NST CD-ROM.
Tooling Up
NST is a great toolkit to have at your disposal. It's portable, runs on a wide variety of hardware platforms, contains many useful tools, and provides access to many network resources. NST also includes CD-ROM-burning tools that you can use to recover data from machines that won't boot (as long as the drives aren't completely dead). If you have little Linux experience, NST provides a good way to become familiar with the OS and its associated security tools. Download a copy and check it out.