i studied the microsoft document you linked.
the expected behaviour seems to be:
your system wakes up, and in few minutes (2-5 ?) any program can call the timer-reset (or standby will occur).
your computer doesn't switch off while there's any HFS serving activity.
when this activity ceases for X minutes, your system will sleep again.
sadly, the documentation doesn't seem to specify this latter amount of time.
Did you make a test with a WOL-Call?
no, and i had hibernate set to "never"
Was the download going on all the time or did you test, how long it takes, that the system goes to sleep after the download is finished?
i manually stopped the download (on the same PC) and waited without touching mouse or keyboard.
after 2 minutes, standby occurred.
As I set my system to a hibernation time-out of 30 minutes, I would like my system to hibernate not before 30 minutes after the last network activity.
if this doesn't happen, it may be because Windows uses a different timer in such situation.
If that's true, it must be a design decision.