Fortget it. PSNLover just enables online play, and in between, maybe even this is not working anymore. Creation of Accounts or purchases in the PSN-Shop are not possible.
Some say they managed it to download demos... don't know if this is true. If you want a full working PSN Account with all it's features, original Firmware is the only way to do it.
P.S.: If you own a Pandora-Battery, you can swap to the newest original Firmware, buy/download your stuff and after this downgrade your PSP again.