[Sony Cross-Device General] serajr:
[MENTION=962182]rayman[/MENTION] first of all, sorry for spamming your thread (If you do mind, please let me know, and I remove this from here)!

XP (F8131) MM, both DRM keys and ota (see screenshots and pay attention their timestamps at statusbar)!

Windows, MM Kernel and the backup of TA partition (made from OP's tool, ofc).

Creating

boot.img:

E:\Android\rootkernel_v5.0_Windows_Linux>[B][COLOR="blue"]rootkernel kernel.elf boot.img[/COLOR][/B]
- Unpacking kernel
Found elf boot image
Kernel version: 3.18.20-perf-g776b104-02151-g3190603
Found appended DTB
- Detected vendor: somc (Sony), device: dora, variant: row
- Unpacking initramfs
- Detected platform: 64-bit
- Detected Android version: 6.0.1 (sdk 23)
[COLOR="Blue"][B]- dm-verity is enabled. Disable? (Say yes if you modify /system) [Y/n] Y[/B][/COLOR]
Disabling dm-verity
[B][COLOR="blue"]- Sony RIC is enabled. Disable? [Y/n] Y[/COLOR][/B]
Disabling Sony RIC
[COLOR="Red"][B]- There is no TWRP template for dora. Install anyway? [y/N] N[/B][/COLOR]
[B][COLOR="blue"]- Found SuperSU-v2.78-201609011115.zip. Install? [Y/n] Y[/COLOR][/B]
Stripping SuperSU app
Adding service entry for SuperSU
[B][COLOR="Blue"]- DRM fix is unsuppported/untested for model dora. Install anyway? [y/N] Y[/COLOR][/B]
[B][COLOR="blue"]- Install busybox? [Y/n] Y[/COLOR][/B]
- Creating new initramfs
- Creating boot image
- Cleaning up
Done

I've decided to integrate SuperSU as well. It's up to you!

Creating

DK.ftf:

E:\Android\rootkernel_v5.0_Windows_Linux>[B][COLOR="blue"]flash_dk TA_F8131_CB512AD0TJ_06122016-2207.img DK.ftf[/COLOR][/B]
- Extracting device key
- Creating FTF file for device F8131
- Cleaning up
Done

1. Unlocked BL (Sony's official way)

2. Flashed custom kernel: fastboot flash boot boot.img

3. Copied DK.ftf into Flashtool's \firmwares folder and flashed it. Flashtool output:

07/011/2016 17:11:49 - INFO - Selected Bundle for Sony Xperia X Performance(F8131). FW release : 1.0. Customization : [B][COLOR="Blue"]DeviceKey[/COLOR][/B]
07/011/2016 17:11:49 - INFO - Preparing files for flashing
07/011/2016 17:11:49 - INFO - Please connect your device into flashmode.
07/012/2016 17:12:03 - INFO - Device connected in flash mode
07/012/2016 17:12:03 - INFO - Opening device for R/W
07/012/2016 17:12:03 - INFO - Reading device information
07/012/2016 17:12:03 - INFO - Phone ready for flashmode operations.
07/012/2016 17:12:03 - INFO - Opening TA partition 2
07/012/2016 17:12:04 - INFO - Current device : F8131 - CB512AD0TJ - 1302-6536_R4A - 1300-5321_35.0.A.1.297 - GENERIC_35.0.A.1.297
07/012/2016 17:12:04 - INFO - Closing TA partition
07/012/2016 17:12:04 - INFO - Start Flashing
07/012/2016 17:12:04 - INFO - No loader in the bundle. Searching for one
07/012/2016 17:12:04 - INFO - No matching loader found
07/012/2016 17:12:04 - WARN - No loader found or set manually. Skipping loader
07/012/2016 17:12:04 - INFO - Loader : S1_Root_de8d - Version : 1299-4832_S1_Boot_MSM8996_LA1.0.1_31-H / Boot version : 1299-4832_S1_Boot_MSM8996_LA1.0.1_31-H / Bootloader status : ROOTED
07/012/2016 17:12:04 - INFO - Max packet size set to 4M
07/012/2016 17:12:04 - INFO - USB buffer size set to 512K
07/012/2016 17:12:06 - INFO - No flash script found. Using 0.9.18 flash engine
07/012/2016 17:12:06 - INFO - Opening TA partition 2
07/012/2016 17:12:06 - INFO - Writing TA unit 00002774. Value : 01
07/012/2016 17:12:06 - INFO - Closing TA partition
07/012/2016 17:12:07 - INFO - Opening TA partition 2
07/012/2016 17:12:07 - INFO - Closing TA partition
07/012/2016 17:12:07 - INFO - Opening TA partition 2
07/012/2016 17:12:07 - INFO - Closing TA partition
07/012/2016 17:12:07 - INFO - Opening TA partition 2
07/012/2016 17:12:07 - INFO - Closing TA partition
07/012/2016 17:12:07 - INFO - Opening TA partition 2
07/012/2016 17:12:07 - INFO - Flashing DK.ta to partition 2
07/012/2016 17:12:07 - INFO - Writing TA unit 000007EC. Value : C0 02 00 02 44 4B 00 00 00 00 00 00 00 00 00 00 B8 1F 52 03 D0 39 6C 60 85 C0 A9 9D FE 4F D1 B8
07/012/2016 17:12:07 - INFO - Closing TA partition
07/012/2016 17:12:07 - INFO - Opening TA partition 2
07/012/2016 17:12:07 - INFO - Closing TA partition
07/012/2016 17:12:07 - INFO - Opening TA partition 2
07/012/2016 17:12:07 - INFO - Writing TA unit 00002725. Value : 32 30 31 36 2D 31 32 2D 30 37 20 31 37 3A 31 32 3A 30 37 00
07/012/2016 17:12:07 - INFO - Writing TA unit 00002774. Value : 00
07/012/2016 17:12:07 - INFO - Closing TA partition
07/012/2016 17:12:07 - INFO - Ending flash session
07/012/2016 17:12:07 - INFO - Flashing finished.
07/012/2016 17:12:07 - INFO - Please unplug and start your phone
07/012/2016 17:12:07 - INFO - For flashtool, Unknown Sources and Debugging must be checked in phone settings
07/012/2016 17:12:07 - INFO - Device connected in flash mode
07/012/2016 17:12:17 - INFO - Device disconnected

That's it. Btw, I have no recovery installed onto FOTAKernel!

You may ask me, how did you install Xposed Framework without recovery?

[B][I]adb shell[/I][/B]
& [B][I]su[/I][/B]
# [B][I]mount -o remount,rw /system[/I][/B]
# [B][I]busybox unzip /sdcard/xposed-v87-sdk23-arm64.zip META-INF/com/google/android/update-binary -d /tmp/[/I][/B]
# [B][I]chmod 777 /tmp/META-INF/com/google/android/update-binary[/I][/B]
# [B][I]/tmp/META-INF/com/google/android/update-binary 3 0 /sdcard/xposed-v87-sdk23-arm64.zip[/I][/B]
# [B][I]reboot[/I][/B]

Ensure to copy Xposed Framework zip to the internal storage.

TRY IT AT YOUR OWN RISK!

I think that this may answers most of people's doubt. So let's keep on topic!