[LG Optimus G Pro] colddecked:
A little back ground, I have a G Pro F240L, and was running the G2 apps V5, and felt the urge to try out kit kat. My journey back to stock though was alittle more complex than the process detailed on this thread. Basically, for whatever reason the KDZ method did not work for me, so after a long search I came across flashing with LG Flashtools (thanks chimmot307!).

My process for going back to stock 4.1.2 was as followed:

1) I had already installed the LG United Drivers from my attempts at using KDZ for flashing. I download the stock 4.1.2 f240L TOT file from here. (Tip: You can save some time by registering for fshare, but its not required. Your download will just be restricted to 100 kb/s, as opposed to 200 kb/s when you sign up for the free account. Actually I didn't want to register for an account, but my first attempt at downloading the file ended in failure, and fshare will not let you download more than once, so I registered for an account and boom it let me download it again, at a faster rate to boot. Anyways...)

2) Download the dll provided by chimmot307 here. This is the dll used for flashing our F240x. There's a different dll that you will need to use LG Flash Tool.

3) Download LG Flash Tool v1.8.1 here or here (thanks WACOMalt!).

4) Download the dll to get flash tool to run here.

5) Install flash tools, after complete, copy the dll from step four into whatever directory flash tool installed to.

6) Follow the guide provided by WACOMalt, which is actually for G2, but the process is the same for f240. Process is also detailed here (with pictures). The second link uses an older version, but the process is the same.

Some areas of concern for me as I followed the guides:

- When flash tool says ready, just disconnect the usb and wait afew seconds. Disregard the download mode warning. Don't touch the power button just take the usb out and leave it in download mode for a few seconds. Plug the usb back into the phone and the flashing will start automatically. Go out for a smoke, walk the dog, or watch the progress bar. I did all three.

- When the progress bar says something like "pass (543 seconds)", the flashing is complete and you can disconnect the usb from the phone.

CLOSE LG FLASHTOOLS AFTER YOU DISCONNECT THE USB!

I made the mistake of leaving it on, and had to go through the whole process again, as well as a panic attack hoping I didn't just brick my phone when I plugged the usb back in to run support tool :eek::laugh:.

- On the phone, choose your language and skip though all the setup stuff because you will have to do that again anyways because you need to do a factory data reset, under backup & reset in the settings menu.

From there I was on a rather early version of the firmware. I think it was v10k. From there to update to 4.4.2, since KDZ and OTA wasn't working for me, I ran LG Support Tool, and that let me update to KitKat. Whew...

Anyways, I am currently on 4.4.2 stock, and was thinking about trying out the Sphinx V1.5. Just a few questions

1) In this post the poster said download the latest sphinx rom and corresponding patched for your device. What is the corresponding patch? All I have is the file SphinX_GPRO_Kitkat_1.5.zip. I don't see a patch. Is the patch included in that file?

2) How is the sphinx rom different from the g2 apps rom? I'm trying to decide if I should wait for g2 apps rom v7 to be final since I trust that dev. Is there a big difference? Is there anything you miss from the g2 apps rom that sphinx rom doesn't have?

3) Does LTE work?

Anyways thanks for listening, hope this post can help someone with an F240 on a custom rom wanting to go back to stock in order to try out kit kat.