That said this is how I flashed and it worked for me!
1: Get the firmware from the opening post I used the T-Mobile firmware.zip
https://dl.dropboxusercontent.com/sh...RuMvPhMiA&dl=1 (not the full RUU) but if your phone is not T-Mobile you may need the first download BehradGH_HBoot_2.15.0000_TWRP_Recovery.rar which includes adb and other goodies along with the firmware.zip inside.
2: Download the One S all in one toolkit here
http://forum.xda-developers.com/show....php?t=1604677
3: Optional as the lastest is included in the latest version of the toolkit but just in case or if you already have an older version of the toolkit you can get the latest TWRP recovery here
http://goo.im/devs/OpenRecovery/ville
My recommendations for file locations are all for making things easier to find
First unzip the toolkit to drive C example c:/one_s in this folder you should see "one s.exe" and a folder called data
Now unzip (or open using 7zip) the firmware and copy the recovery.IMG file inside of firmware.zip (for non T-mobile its inside of BehradGH_HBoot_2.15.0000_TWRP_Recovery.rar) to the recovery folder example c:/one_s/data/recovery (optional if you needed to dowload it copy the TWRP recovery IMG to the same folder).
Last step before beginning the upgrade process copy FIRMWARE.zip into the data folder c:/one_s/data
I recommend using an original USB cable and not some aftermarket or generic POS!
Now the fun begins. Start the all in one toolkit c:/one_s/One_S.exe
And choose reboot to bootloader make sure your phone shows fastboot usb
First we need stock recovery so select flash "your own recovery" in the upper right box and and the click on "flash recovery" when it shows you the file explorer box choose the stock recovery that you extracted before it will do its thing and should show finished okay in the command prompt window after it says done reboot to fastboot.
So far so good you should be back on the bootloader.
From the toolkit main screen in the lower left corner menu select "Flash a factory RUU zip" and click "run"! It will give you some BS message about needing a locked boot loader etc ignore and continue, it will now take you your phone to a black screen with a silver HTC logo and will ask you to locate the "RUU" choose the firmware.zip file and it should start on its own if not open a command prompt from the c:/one_s/data file and type in fastboot flash zip firmware.zip and it should do its thing when it says okay and finishes choose reboot into bootloader if it doesn't work and stays on the HTC screen with the green line hard reboot with power and volume down and go back into the fastboot menu.
Last but not least from the toolkit flash recovery again use the TWRP (S4) or if needed "your own recovery" (select the TWRP IMG that you downloaded) click "flash recovery" and wait for it to say done.
Reboot the bootloader and choose recovery from the menu happy flashing don't forget a full (data/system/cache) wipe might be needed before flashing the ROM.