Just to ask, wouldn't this be a bad idea for people that don't have internet 24h. Like Dial-Up or people with Capacity Limit (Like 5GB per month). It always has to download the file from the internet and if it's not working or the internet dies for maybe some hours, you can't play the game.
I thought maybe to do like looking at the date & time of the pc and see how much difference is from the actual release and now. If it's too big, it closes the app or says it's expired. Just the problem would be, you could bypass this by setting the date back and presto, it's working again.