1. go to
http://www.fileplay.net [fileplay.net]
and register for a free account and verify that account.
2. go to
http://www.fileplay.net/keys/55/crysis3-alpha
and request for a new key and your key will be displayed on the screen so copy and have it.
3. Download origin or if you have origin , login with your email and password.
if you dont have account in origin , create one.
4. go to redeem product code and paste that product code which you got from fileplay.net and
click redeem.
5. the game will appear in your origin account and the hover over the game and click pre load.
works