This is the stock firmware of VX2, for Windows OS only. The firmware has two RAR files, please download them in a folder, then you can decompress the files.
Here are the packages of VX2 Celeron Mini PC dual system installment firmware
Part 1: VX2 1800 VX2 1900 Windows 8.1 Mini PC Stock Firmware.part1
Part 2: VX2 1800 VX2 1900 Windows 8.1 Mini PC Stock Firmware.part2