How to Revert to Stock ROM for HTC Desire 816?

Hi guys!
I recently installed a nightly custom ROM(CM 12) from CyanogenMod for my device(HTC desire 816).
Now I wish to revert back to stock ROM from htc.
Please tell me the steps to do it because I cannot flash the stock ROM using the CyanogenMod recovery(Error: Signature Verification Failed) and I cannot find any other custom recovery for my device.
Please help me out ASAP!!

Revert Back to Stock Kitkat

Pre-requisites

1. Old Kitkat stock rom.
2.TWRP 2.8.6.0
2.Faith and patience.

Steps

1. Download the zip from here
2.Open the stock kitkat in Winrar
3.Paste the files in zip downloaded from above to corresponding places.
Like system folder and META-INF in root of archive
4.Flash this edited stock rom in twrp after factory reset.
5.Wait till installation completes and let it reboot.

Voila ...You are on Kitkat now.

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Please Help! How do I revert back to my custom ROM? [Asus Zenfone 5]

I yesterday Flashed Cynogenm Mod 12.1 on my Asus Zenfone 5. This was the first time I ever flashed ROM on a device. My device runs fine but both of my sims are not detected!. Also, root access is not enabled even when I changed the root access to apps and ADB from developer options. Whenever I open SuperSU it says "There is not SU binary installed, and SuperSU cannot install it. This is a problem! If you just upgraded to android 5.0 you need to manually re-root - consult the relevant forums for your devicce!" . I am in great trouble! please tell how can I switch back to my previous ROM or if the sim issue can be fixed. Please reply quick! Thanks!

Can I revert to F350L 10d from F350L 20b

I have LG G Pro 2 , F350L 10d and I am planing to upgrade to F350L 20b ( which is Lollipop I think). I will do that through LG PC suite, easier and allow easy back up.
My question is , ca I revert back to F350L 10d ( kitkat 4.4.2) or I can not ?
What is the main differences between the 2 of them?
Thank you in advance

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