First install Rebug 3.55.4 from XMB on top of OFW 3.41, then extract your eEid Root Key if you ever want to convert to DEX and then install Rebug 4.41.2 by following the guide below:
1- Make NOR/NAND dump (optional):
Install latest version of multiMAN (4.40.00), plug in a FAT32 formatted USB flash drive into the right USB port, launch multiMAN under Games and go to mmOS > Press [O] on any file > Open in HEX viewer > Press [SELECT] > Press [START] > Export GameOS LV2: Select No > Export HV LV1: Select No > Export FLASH: Select Yes
2- Install Rebug 4.41.2 from XMB:
Download Rebug 4.41.2, verify the md5 hash, rename the PUP to PS3UPDAT.PUP, put it on your FAT32 formatted flash drive in PS3\UPDATE, go to System Update and Update via Storage Media. Make sure there's NO original game disk in the drive and that you DON'T Update via Internet or else you would risk installing OFW higher than 3.55!
3- Enable QA:
Install Rebug Toolbox from Package Manager, launch it under Games, go to Utilities and enable QA. This is to ensure easier and safer downgrading.
Make sure you use the latest version of mM (4.40.00) because it's the only Backup Manager compatible with 4.41 CFW.