I was going through your screenshots this morning and noticed that you have a large number of "alert flags::
That seems like a large number of changes in so short of a time period.
Also, you have a period there where the computer was "on" but with very low or no data usage but still getting alert flags.
Was the computer on and simply not being used or was it in hibernation ?
For the time period in question peek at the "Alerts" tab and see if the flags were for software changes or the more normal dns changes.
As a comparison here is mine for an entire week:
Its most likely nothing but I'm curious what all the activity is about.
I get a lot of flags, too, and most of mine are due to "DNS server settings changed". On July 29th alone I had it change five times in a span of nine hours. This is with my desktop, connected directly to the modem. I shut down the modem every night, so I might expect it to do it every time I boot the modem, but four times in a day? Odd. I don't have any issues, so I never bothered to concern myself with it.
It's not recommended. When not streaming, and even when turned off (actually standby), your DirecTV receiver will still use the internet for some things. The data usage varies, but can be considerable, and there's no way to control it.