It would seem that I can download the 5.5GB trial of Crysis Wars; so I was thinking of downloading that now until I get a copy of Crysis Warhead. Once I get the Warhead, then can I activate Crysis Wars? 
Squibby, he asked this at first, and yeah he'll have to buy it anyway. He can just use it to install Crysis Wars, and then later on buy Crysis Warhead just for its key. That trial version is the same as a retail one, it just doesn't includes a CD Key, he can only play LAN games.
Umm... probably not, but feel free to try. If it does, you may have found a way to make this mod 100% free, so no one will complain
Well CoffiNail, a Crysis Wars mod called
Casus Belli suggests the trial version alone of Crysis Wars would be enough to play online that mod, but that's
because they're bypassing the CD Key check, which probably isn't an option for the MWLL devs.
And Cherno, that must be from an early trial Crytek made. They had a system to generate keys in their website to then use in that trial version, but the keys only had a limited time.
Oh and est1895, yep those links are ok. You can then download the Crysis Wars 1.5 Patch and install it. Then you can start installing MWLL. You won't be able to play online until you have a Crysis Warhead CD key, which you have to buy.