Crysis 2's in game DLC retailer "Download Content" and the manual download option via gamesas.com has been discontinued. Note the latter was restored yesterday after I requested it be put back.
According to GSI-JGun @ https://secure.gamesas.com/forums/viewtopic.php?f=40&t=43056
"The store won't work any more and thus the history is blank". He also states: "Any DLC you previously owned would be automatically downloaded for you the next time you install the game".

However with all do respect I have no idea who GSI-JGun is and how he got this information.
Therefore I would advise all Crysis 2 DLC owners to backup their existing dlc folder in your system if you already have it or download it from gamesas.com while it is still there.