What firmware are you on? I remember the spoofer not working on Rebug FW which is kind of silly considering they're the ones who made it. Just install it like any other PKG and then follow the on screen instructions, it's really not that hard. Once it's installed, make sure that both PS3's are on the same firmware, you can data transfer from higher firmwares to lower but not the other way round, then just follow the on screen instructions for the data transfer, it's not that hard either.
Yes it does, I did a transfer yesterday with a save game.
Okay so at least it doesn't sound that hard

I have one PS3 with 4.00 OFW and the other PS3 is on regular 3.55 KMEAW CFW.
I wanted to do CoD cl again but I was trying lvl0 method and lost all my game patches.
And now I have to do a data transfer from my PS3 4.00 OFW to my PS3 3.55 KMEAW CFW to put the official CoD online patches on the 3.55 CFW so I can put the challenge lobby patches on and then do a reverse data transfer over to the 4.00 OFW.
Would I have to uninstall the spoofer before I do a data transfer back over to the 4.00 OFW and it would be okay?