Mac App Store stops downloading after the screen goes to sleep

This is a complaint or some sort of bug report. Please don't tell me I need to update my Energy Saver settings (yes, the "Enable Power Nap while plugged into a power adapter" is checked), or install Caffeine. This post will be kind of long, because I want you to understand my frustration and pain.

I understand that with Mountain Lion Apple introduced Power Nap. According to this article (http://support.apple.com/kb/HT5394), my MacBook Pro Retina Display with Mountain Lion, plugged in to an AC outlet, should be able to to the folliwing while sleeping:

"When your portable Mac is connected to a power source, it also downloads software updates, makes backups with Time Machine, performs Spotlight indexing, and can continue Mac App Store downloads. It also updates Help Center."

Last night I bought Call of Duty 4 (7.35 GB), which seems to be larger than Mountain Lion itself, and left my laptop downloading it. I didn't even close the lid. The screen saver started, and after a couple of minutes, the display went to black. I didn't get off my bed to check it out, because I trusted Apple's technology. Anyways, it turns out that this morning, when I woke up, unlocked the laptop and the download on the Mac App Store said: "Waiting...". A couple of seconds after I unlocked the latop, it started to download again. Was it waiting for me to wake up? It's not capable of downloading an application without my supervision? It didn't make much progress from where I left it at lastnight.

Is there a bugtracker or something where I can submit a bug report or something? Is this a known issue and they are working on it? Is this the behavior I should expect from Power Nap?

Thanks!