You can find the image here:
https://www.vuplus-community.net/board/threads/black-hole-3-0-9-f-vu-zero-vu-zero-rev-2-0.39702/
Download the image, and unzip it. Load the vuplus folder, onto a FAT 32 formatted USB stick.
Power off Vu+ Zero using the switch, at the rear of the receiver.
Insert the USB Pen Drive into the USB socket on the back.
Switch on Vu+ Zero.
The white LED, on the left side, of the front panel should begin pulsing, indicating that the image is loading.
Once the image has successfully loaded, the pulsing will stop and change to blinking on and off.
When the white LED is blinking, on and off, switch the receiver off, using the switch, at the rear, remove the USB stick, then power it up again.
At which point are you experiencing a problem?