I noticed that many people want to get recovery working on Marshmallow-Beta. Most people don't want to loose there data, settings ....
So I thought about writing a little Tutorial.
boot.img with included Recovery
TWRP for unlocked Bootloader
FTF of the .264-firmware (you can download it via XperiaFirm (keep in mind selecting your Phone (e.g. D6503))
flashtool and it's latest update
A few GB space on your SD-Card
The first thing we need to do is to backup our Data, but How to do this without Recovery, TitaniumBackup isn't a good solution.
So .. one way would be to flash a boot.img, so we can boot a recovery, which is included into that file
Step4: Connect Phone to PC and backup your Data From internalSD
Step1: Shutdown your Phone (you should have at least 50% battery for a safe flash)
Step2: Connect your Phone to your Computer, while pressing the Volume UP Button (if you have a blue light you're now in fastboot-mode)
Step3: flash the boot.img (fastboot flash boot stock-17.1.1.A.0.402-sirius-repack.img via cmd) NOW YOUR PHONE CAN NOT BOOT TO MARSHMALLOW ANYMORE
Enter recovery and make a backup
Flashing new bootloader
Step1: reboot your phone (fastboot reboot), then press the vol down Button repeatedly, until you enter the recovery.
Step2: make a backup and select everything, but boot IMPORTANT !
Step1: shutdown your phone completelyFlashing TWRP
Step2: start flashtool and select the thunder symbole + flashmode
Step3: select your downloaded FTF and select wipe Userdata+Apps-Logs
Step4: plug in your phone with vol+ pressed, so that you're in flashmode
Step5: flash firmware
Step1: Shutdown your Phone
Step2: Boot into Fastboot
Step3 Flash TWRP for unlocked bootloader : fastboot flash recovery recovery.img
Step1: Shutdown your phone---
Step2: Boot into Recovery (hold Power and VolDown, release Power when phone vibrates)
Step3: flash MM-Zip
Step4: restore your Backup
Step5: restore Internal-SD-Backup-files to InternalSD