I selected to rent and watch now instead of rent and watch later. I tried to watch it now and it said it would be available in 6 hours or something silly like that (certainly out of the realm of NOW ) Anyway.... I tried to play it several times and the time it said I had to wait did go down. 5 hours to 3 hours to 2 hours and so on but this was an all day and next day kinda thing. I guess I was downloading it for 2 days. I figured id just get up the next day and try again NOW the movie has been removed from the rented section all together. It's gone...my time is up!!! I haven't even watched it yet. It was downloading for 2 days. I know I can adjust my settings to download a lesser quality and thats fine for NEXT time but I paid $5 to rent a movie that I never started watching because it never finished downloading! I wonder if because I selected Rent and Watch Now (joke) it assumed even though it was still downloading that it started my time at initial time of purchase? If so that's crap too. Anybody have similar experience?
Nothing is stored on the Apple TV. Once you select to watch now it will start caching the rental and the clock starts. If other content is accessed or ATV goes to sleep then it will be flushed and need to load again.
It needs to load a portion before playback begins and that time will be dependent on your network. (1080P requires 8mbps, 720p needs 6mbps for instant stream etc).
If you wish to store and/or have a slow connection that you cannot upgrade, download to computer and use home sharing or the aforementioned lowering of resolution on ATV.