I use a tool called bootcd which produces a bootable ISO 9660 images. Sometimes I need to make a small change in one of files in the ISO image

Now I am wondering how can I edit the ISO image to make that change without going through the entire process of create the ISO image from scratch.

I use "make_iso.sh" or "make_iso.bat" to do all my iso's.

They are found in any Slax/Wolvix/GoblinX iso's/tar.gz's

In Ubuntu-8.04, I just double-click make_iso.sh, choose "run in terminal", and then give it any name ending in ".iso" and bang! New Iso!

To extract, in Ubuntu, just right-click, select "extract here"(xarchiver?), and bang! extracted iso!

If you get an error message when extracting, use gmountiso, mount the iso on "cdrom0", and select "jump to", then when the browser opens, choose "select all", "copy" from the "Edit" button up top, and copy to a folder.

You can use ISOMASTER to add or delete files from an iso, but I tried editing a cfg file and it didn't work...

Note-read the .sh/.bat, cause they have to be placed and ran from the boot folder...
so, put the make_iso.sh/.bat files in the boot folder, which must contain a isolinux folder, and then make either one executable(right-click/permissions/check "make executable" box).
Then either invoke thru the command line (./make_iso.sh) or just double-click as above.

My latest download (ISO-USB-KIT.tar.bz2), which has all this, is a great tool, check it out as well as my other stuff.

Always have "show hidden files" selected in your file browser whenever editing iso files, etc, so you can delete the backup files that appear(isolinux.cfg vs isolinux.cfg~), they will corrupt the iso!