The best scenario would be if you had your original NAND dump
you can flash it with every newer version of the '
Despertar del
Cementerio' by Dark Alex, if not...
download the 5.00 update eboot from for example
HEREand copy it to /PSP/GAME/UPDATE/UPDATE.PBP
(if it does not exist... create it.)
in the Game menu now you should be able to find the update.
ELSEwhen what i propose sucseeds you cant convert your Battery back to a normal batterywith your PSP!!!!If you can
build an DC8That allows you to flash OF 5.00 without the Network update.
After that you should be able to update to 5.02 OFW.
Good luck to you!