MPHDowngrader.zip corrupted?

Hi guys I've got a few questions (yes i'm a girl so no mocking :) )
I just upgraded my psp from 1.52 to 2.0 so i can downgrade it. That part went fine.
I'm using the post 'PSP V2.0 to v1.5 Downgrade guide' btw.
So i downloaded the 1.5 file and the MPHDowngrader.zip
and as the Guide states, Norton detects it as a virus. But its detecting a file called PSPBRICKER in the zip and removes it. Why would this file be in there? WHen i open that zip and read the README file, it makes no metion of a file by the name. So i'm wondering if the zip file as been corrupted?
Also the README says to put the OVERFLOW.TIFF file into your PHOTO directory- that file is not in the zip file.
What is going on? I'm worried about the missing file the file my norton is deleting by a different name. Has anyone else done it recently and seen these errors?

oh and i turned off Norton so it wouldnt detect and delete it but there is still no overflow.tif file in the zip file. :(

If you have the same MPH downgrader I did these instructions should work....

- Create a UPDATE folder in PSP/GAME/ folder of your memory stick
- Copy EBOOT.PBP (update 1.50) in UPDATE folder
- Unpack MPHDowngrader.zip
- Copy overflow.tif in your PSP/PHOTO/ folder of your memory stick
- Copy h.bin in root of your memory stick
- Copy index.dat in root of your memory stick
- Plug the AC adaptor


Then, enter in VSHELL PHOTO MENU, this will launch Version Changer.

AKA

-Make a folder named UPDATE in your games folder of yout PSP
-Place a 1.50 EBOOT.PBP (you can get it at psphacks.com) in the UPDATE folder
-Put the overflow.tif in the PHOTO file on your PSP
--Put the h.bin file directly onto the PSP before opening any other files
-Put index.dat with h.bin
-Plug in the AC adapter
-ON YOUR DISCONNECTED PSP go to the photos section, which should glitch it up
-Restart your PSP and run UPgrade 1.50 from your PSP Games

if you have not found a way yet, this is a better method
get the tiff exploit eloader from fanjita's website,
get PSPsetX from team emergency exit
get a 1.5 eboot from either UMD disc(rare) or pspupdates
install them using readmes,
run eloader
put the plug in psp! (make sure charged as well)
run PSPsetX
choose the downgrade option
exit PSPsetX
go to system settings; system info, your psp version number should be 1.0
run the 1.5 eboot from game menu
it will now update the psp... backwards
it may still do the error at 99% dont worry wait 20 seconds then hard reset