1) Use small rs232 board connected to receiver and use rs232 cable connected to computer.
2) Power on the box
3) Run UpdateAllFlash.exe on PC and choose the correct com port
4) Open "duo boot.bin"
5) Click update, it will show progress, wait it to finish.
6) Remove small rs232 board and cable
7) Power off, and power on again, box will show starting, now you can use usb, update the image you want with USB Stick
(IMPORTANT : Use LAPTOP with WinXP OS and REAL RS232 port)