[Huawei MediaPad X2] dimitarnc:
Full steps I made:

I had 701L device [MENTION=599517]b21[/MENTION]1 KangVIP.

first downgrade to B112 for 703L stock:

1. extract in the directory with ADB the 5 images from 703L B112 (BOOT.img, CUST.img, RECOVERY.img, SYSTEM.img, USERDATA.img) + TWRP 5.1.1

2. to not loose time start copy the 703L B112 dload folder to a SD card. Put the Universal Cust B112 on the SD card too.

3. put the phone in fastboot and execute the following commands with the prepared images in the ADB folder:

fastboot flash boot BOOT.img

fastboot flash cust CUST.img

fastboot flash system SYSTEM.img

fastboot flash userdata USERDATA.img

fastboot flash recovery TWRP-ENG-5.1.1.img

fastboot reboot (immediately press vol. up & down to enter the flashed TWRP)

4. In TWRP format everything except the external SD card (dalvic, cache, data, internal storage, system). Insert the SD card prepared in step 2. Flash the Universal CUST B112. Go to home in TWRP, choose reboot & power off. Put again the phone in fastboot (Vol. down + power until the white screen)

5. In ADB folder execute:

fastboot flash boot BOOT.img

fastboot flash recovery RECOVERY.img

fastboot flash system SYSTEM.img

fastboot flash userdata USERDATA.img

fastboot reboot

remove sdcard immediately.

6. B112 for 703L boots - do full reset and disconnect the USB cable. The Recovery will load and reset. Boot again in the system. If the reset failed, try to reset again, sometimes it succeeds from second time.

7. Inser the SD card prepared in step 2 again. Choose local update and let the Recovery do full dload of the B112 image from the SD card. The USB cable should stay unplugged. When ready the phone reboots. Immediately put it in fastboot.

8. Flash again the 5.0 TWRP and the Universal CUST B112 from the SD card, reboot in fastboot and put again the original B112 recovery, boot straight in the fully installed B112 for 703L.

9. The SD card should be removed. The USB cable disconnected. Do full reset again.

10. Now you have the clean stock B112 for 703L running on the 701L phone. Check everything is correct in the about info (amount of RAM, storage etc.)

11. From here you can follow exactly the downgrade guide to convert the phone to B005 for 702L.

12. extract boot.img, cust.img, system.img, userdata.img, recovery.img from gem-702l B005 stock rom, and fastboot flash all of them.

13. flash TWRP 5.0 and boot it

14. flash Universal CUST B112 from TWRP

15. fastboot flash the B005 702L recovery.

16. boot the system and do full reset (SD card should be out and the USB cable disconnected). Repeat if it fails from the first try.

17. Extract files from the downgrade pack. Put the dload directory in your SDcard. Manual update it. It should go through 100%.

18. After the phone boot up, copy the full gem-702l B005 stock firmware to your SDcard, manual update it. It should go through 100%

19. fastboot flash TWRP 5.0 and boot it

20. flash Universal CUST B112

21. fastboot flash original B005 702L recovery.

22. Boot the system and full reset again (SD card should be removed and the USB cable disconnected)

23. You are now in clean stock B005 image for 702L running at your 701L phone and the battery is charging! The downgrade script was the magic and the need to use the Universal CUST B112 to be able to run correctly the foreign ROM.

Now to return to B005 701L stock image for Eu:

1. fastboot flash the 5 images from the B005 701L Eu ROM (boot, cust, system, recovery, userdata)

2. fastboot flash TWRP 5.0 and boot it

3. flash in TWRP the 701L-Cust.zip backup I find in the Russian 4PDA forum (attached in the above posts)

4. fastboot flash the original recovery for 701L B005 Eu

5. Boot the system and do full reset (sd card reoved and USB cabl disconnected) If fails repeat it again.

6. You are now completely stock and original. I tried to full dload flash B005 701L without success. It was however not needed because the system runs fully stock and original. And the battery charges!

I want to Thank again to everyone to this forum for the enormous amount of information that made this possible.

Attached is the downgrade pack