Can't rebuild the changed firmware

```
What steps will reproduce the problem?
1./home/pc/Desktop/fmk/extract-firmware.sh /home/pc/Desktop/fmk/lc2.bin
2.Changing some files of the extracted firmware
3./home/pc/Desktop/fmk/build-firmware.sh /home/pc/fmk

What is the expected output? What do you see instead?
Expected output: Rebuild the changed firmware in this directory:
/home/pc/fmk/new-firmware.bin like it's written in the instructions of the
firmware-modkit
Seeing instead: Preparing tools ...
Building new squashfs file system... (this may take several minutes!)
Squahfs block size is 64 Kb
sudo: /home/pc/fmk/rootfs: command not found
Failed to create new file system! Quitting...

What version of the product are you using? On what operating system?
Product verion: Firmware Mod Kit (build) 0.99
OS: Ubuntu 10.04 LTS -Lucid Lynx-

Please provide any additional information below.
I only changed the version.txt file and a few images of the extracted firmware,
which have exactly the same resolution as the original files. Tried with
[-nopad] and [-min] too, but i just get an error message saying:
cat: /home/pc/[-nopad]/logs/config.log: File or directory not found

Could someone please help me with this problem? Thanks in advance!

```

Original issue reported on code.google.com by `Michi....@googlemail.com` on 16 Jul 2013 at 12:43

Start by reading extract-firmware.sh and build-firmware.sh, then reproduce the command sequence with the reported /home/pc/fmk paths. Inspect how build-firmware.sh invokes the squashfs tool and handles rootfs, including the -nopad and -min options. Done means rebuilding the modified firmware into new-firmware.bin without the reported command-not-found or log-path errors.

Written by the indexing model from the issue text.