It looks like this device is just a network storage device which needs a computer to access. If you can find a network storage device with DVR capabilities than you can use your VCR/DVR Ir commander to record to it without the use of a computer.
Right now it look as this device will need a computer and some kind of recording software to store the video on it. There has to be a way for the video receiver to get the video to a computer and then the recording software can save it to this device.
Yes it has USB ports and supports flash drives, but I think what this does it just puts the flash drive on the same network storage device.
Using your computer: You can setup the computer to not go on standby and actually should be able to tell the network card not to fall asleep in the device manager. Then you could just turn your monitor off to save power.
Almost anything can be told or setup to not go into standby.
That is one way of doing it. I'm sure the other users here could come up with some more ideas. But it really looks like with the system that your planning on getting really needs a computer to function properly.