[LeEco Le 2 Questions & Answers] joebah:
Finally!

Okay, so I downloaded the file S3_X626.rar per the second part of the instruction - took a while but in the end it resolved all my problem. Here's my experience (I want to document before I forget about the details as it seems with this issue you need to get everything right to unbrick the phone)

So my phone screen is mirrored right now, I can kind of navigate around but have to guess where to touch the screen to go into apps and settings. Also, the baseband, EMEI and just about everything is missing. Clearly this was sort of a temporary ROM that gets the phone back into a semi ususable state. In fact, it took me a little while to figure out how to shutdown the phone again! (necessary for the next step)

After unzipping S3_X626.rar - it created a folder called "乐视S3_X626". I also got a bunch of warnings from Windows Defender about virus/Trojans etc - I ignored them.

I booted the phone in fastboot mode per instruction (Vol -, Power), and the familiar black screen with Chinese characters showed up on the phone. I then plugged in the phone into USB. By now my PC fully recognizes the X626! So no more annoying connect/disconnect problem.

I ran the file 开机oem解锁-音量下+开机键_读取Devices.bat. The Dos prompt did a bunch of stuff (I guess it's unlocking the bootloader?) and then a text file "Devices.txt" is generated in the folder. I guess this part just figures out some sort of ID of the phone? Anyway, onto the next step..

I ran 刷机.bat, immediately I got an error on the dos prompt and had to exit. So it turned out that for this step, I need to change the folder name from 乐视S3_X626 to S3_X626 by removing all the Chinese characters - which the instruction said though it wasn't very clear when the author wrote it. The dos prompt went through some sort of flashing process which took like 10 mins. When it was done, I unplugged the phone - and had to hold down the power button for a while to reboot (at first it just got stuck on the bootloader screen)

The next part is where things got interesting. So now the phone rebooted normally and the "EUI" logo showed up. Then it froze. So I rebooted the phone again, and this time the EUI logo showed up and it started to initialize the app (I think 15 of them). That took about 10 mins - thankfully I had my device all charged up before I did all this! Finally, we got to the setup screen, put in my Sim Card and connected to Wifi - skipped the finger print set up stuff and finally I am back to the home screen. Also, the EUI is now in version 5.9.020S (I was on 5.8 earlier), with baseband, IMEI and everything! Android 6.0 of course. Everything works as it should.

So this has been one heck of an effort to unbrick. To be honest, I was about to throw away the phone had it not been for the fact that it's the holiday seasons and I had a lot of down time on my hands :p. Must have spent a good 15-20 hours messing around with it. Definitely the USB connection and flashing were the hardest to figure out as there are all sorts of different instructions on the web on how to do this and there doesn't seem to be one right way of doing it - though I would have to say that the tickernel blog / OS_man instruction (not sure who owns the IP to this one but thanks guys) is the most helpful. My guess is if your phone is bricked and tried to copy my instruction word for word, there's still a good chance it won't work for you! Anyway, I figured documenting my experience on XDA would be helpful because at least you get to know what will happen if you get a step right (or wrong) - I was mostly in the dark when I did this. Merry X mas!