God of War PSP

My brother just got a shiny new God of War PSP. I have custom firmware on my million-pound phat, and I've downgraded a few PSP's before, so I say, "hey, Ill downgrade that bad boy for ya" So I sit down and go through my whole pandora process, and insert the magic memory card and pandoras battery. The green light turns on. ok, that's good...but for some reason, the PSP is not recognizing the magic memory stick, but ONLY when it has the pandora's battery in...any help?

*edit*
so, now, for some reason, the PSP has decided to recognize the memory stick...new problem though. It says..."Install initialization... OK
Reading IPL... OK
Verifying ipl... Failed -> Not the expected IPL"
I expect that this is a common problem, considering I've faced it before. I've tried replacing the IPL like before, and I'm still getting the same error...

*edit*
Nevermind! After a few hours of trying the same thing over and over again with slight variations, something clicked, and I got the installation screen!

glad you get it to work but you should check your magic memory stick or use a newer version of despertar del cementerio, cause I had no trouble with my GOW psp