The only reliable link that I could find is to this software:
Not sure if this will do what you want though. From what I'm seeing PVF is an audio format. Couldn't really find anything for video files. Hope this at least helps to point you in the right direction.
As far as powering the device down goes, I bought a CCTV kit a few months back and had to move it around for renovations to a relatives business. I couldn't find a power button either so I just turned it off at the mains and pulled the cable out. I'm not sure if this is what they intend but If they wanted it done any other way then they could have included a power switch or a button on the remote.
Hope this helps a bit at least