Yeah, D-Client just unlocks SE phones as far as I know. And Total Multiserver does flash/debrand, but doesn't seem to support W580i or CID53.

Scook94, just to confirm, you flashed your K800i with CID53 with new CID53 firmware? Were the steps you took similar to this CID53 tutorial Flash K800 CID53 with K810 software CID53 (for begginers) - Top Sony Forums ?

Thanks