I'm gonna leave this up but you probably use this instead:

http://forums.nexusmods.com/index.php?/topic/1035988-unlock-all-second-wave-options-modlet/page-5


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Just a simple Upk hex edit that Unlocks Second Wave options.

To Install:
1- Go to /XCom-Enemy-Unknown/XEW/XComGame/CookedPCConsole
2- Rename XComGame.upk.uncompressed_size to whatever
3- Rename XComGame.upk to XComGame.bak or whatever
3- Copy the XComGame.upk file included into the /XCom-Enemy-Unknown/XEW/XComGame/CookedPCConsole folder.
4- Start a new game.

Thanks to Amineri for finding the hex code.
http://forums.nexusmods.com/index.php?/topic/1035988-unlock-all-second-wave-options-modlet/