Mine wasn't downgraded and yes it's 3.55 KMEAW.
If I'm understanding this right... I have to install Rogero CFW 3.55 before Rogero CFW 4.30?
1- This CFW doesn't have LV1 checks disabled and can't be installed on Downgraded PS3 consoles unless you have Dehashed/Reset Syscon Properly (if you're not sure about your PS3, Dehash it anyway to avoid any risk) Link ----> Dehashing Tutorial
2- Always make a NOR/Nand dump using multiMAN or memdump before installing any CFW to have a recovery backup in case of any bricks.
Having a valid NOR/Nand dump is an essential step before upgrading, because you will always have a way to recover (using hardware flashers) when you have a valid dump.
** A Hardware Flasher alone without a valid dump may not fix your bricked PS3 **
3- The QA flag must be always Enabled on your PS3 for safer upgrading/downgrading operations. Link ----> toggle_qa.pkg
4- Always use the Recovery Menu while installing this CFW to avoid possible bricks (XMB update works, but Recovery Menu is safer).
5- Please Check the MD5 of the downloaded PUP file before installing any CFW to avoid possible bricks.
6- DO NOT HAVE DISC IN PS3 WHEN UPDATING FIRMWARES..As the PS3 will take the UPDATE from the DISC First.
7- You need to already be on 3.55 to install this. Installing from any firmware other than 3.55 will simply not work. (In regards to consoles on OFW)
You can find everything that you'll need to update below.