yea you can mannualy flash it
go to the zgemma website
head for the downloads
look for you box
pick your firmware
download it
get a usb
formate the usb to fat32 (windows) or ms-dos (fat) (mac)
extract the zip file
place the zgemma file in to the root of your usb
unplug it
turn your box off at the rear (white switch)
plug in the usb
turn the box back on (white switch)
wait until the lcd screen says USB
press the front power button until it says FLSH
wait
once done remove usb