Signature verification problem. HELP

[Creezy18]

Trying to downgrade from ZVJ to ZVD so I can use the CM 7.2 ROM, but after downloading "update.zip" & putting at root of sd card, I get this message when I apply sdcard :update.zip -- E:failed to verify whole-file signature

 

[thekraven]

You have two options..

Easy route, boot to recovery, full wipe, flash rom + gapps , then flash the zvj / zvd patches here: [Patch's]ZVJ to ZVD & ZVD to ZVJ Flashable zips(Optimus S) - Android Forums at AndroidCentral.com
or use a stock recovery to flash the update.zip.

 

[Creezy18]

I'm really sorry, but I'm kinda like a newbie here trying to do it all by myself. How do I "Easy Route" & is it the ZVJ to ZVD patch I use or ZVD to ZVJ patch.