Read the readme.txt in the package. All you do, is download the xtreme 5.2 package. Pick which verison you want (a,b,c,d), put that in a directory with samtool.exe, orig.bin (your hitachi original firmware), and xtreme52.bin.
Then type: samtool orig.bin xtreme52.bin
Then follow the tutorial on how to flash your the version of samsung that you get. You dont need to make a backup of the original samsung firmware, just flash it.
Caster.