Here is the download address:

http://www.mediafire.com/download/sczh3w7x2m8ketg/OPEN_C(European_Standard)_SD_card_upgrading_instruction_&_software_package-251920B0788FFOS_OPENCV1.0.0B05.rar

The unzip code is geekbuying.com

Instruction of ZTE OPEN project SD card upgrade
Ⅰ Cautions：
The software version and pictures in this document are just for reference only. Please use ZTE handset support website provided version to download software, moreover, SD card upgrade only allows upgrading between the same version and from low version to high version.
1) Before you begin:
a) Please back up all user data of mobile phone, including Phonebook, Messages and so on;
b) Please make sure the mobile phone can be normally powered on. Otherwise it may cause download failure;
c) Take out SIM card and check whether update.zip of SD card is in accordance with to be upgraded mobile phone; copying update package to update.zip file before upgrade.
d) Please check whether the battery power is enough (2 cells more), if the battery power is not enough, please charge the mobile until the battery power is enough; Do not execute SD card upgrade while charging in case losing data or the mobile phone crashes during downloading.
2) Do not do other operations and do not take out battery by force during upgrading.
3) It will take 1-2 minutes to finish SD card upgrade. If the upgrade is invalid, you can contact local ASC.
Ⅱ Steps of SD card upgrade:
1. Download upgrade package and copy the software to sdcard
a) Open the SD card upgrade package which is downloaded from ZTE website, check whether there is a update.zip file( The picture and file name are just for reference only), as picture 1-1 shown below:

b) Copy whole update.zip file to root directory of micro Sd card (TF Card)

2. Power off mobile phone, and then hold the power key and volume up key simultaneously to enter into firefox OS recovery mode, as picture 1-10 shown below.

4. Press side down key to move down until move to “apply update from sdcard”, as picture 1-11 shown below:

6. Press power key Choose the downloaded update package update.zip after entering into directory of T card,, as picture 1-12 shown below.

7. The upgrade will be completed after 1-2 minutes
8. Select reboot system now