Making ROM without flashing to device

Instruction's for making ROM with out flashing to device

first you need a linux box to mount the files

EDIT: 
it has been reported that MagicISO will extract the files from the 
.rfs file system images.

extract the Odin tar to your linux desktop
make a tmp directory for the mount point
open console 

Code:

CD Desktop

mount cache.rfs

Code:

sudo mount -o loop cache.rfs tmp

copy /recovery/sec_csc.zip to desktop
unmount cahce.rfs

Code:

sudo umount tmp

make a directory for the system files
mount factoryfs.rfs

Code:

sudo mount -o loop factoryfs.rfs tmp

copy the system files to the directory for the system files
unmount factoryfs.rfs

Code:

sudo umount tmp

now move the system files, sec_csc.zip, modem.bin, zImage to the windows machine.
place the system files in ROM/system
place sec_csc.zip, modem.bin, zImage in the same directory as deoall.bat
then run the script.