WaW map packs (ALL of them) are working fine for me. I unlocked them ages ago using Yaris Swap 0.4, Sounds like something is wrong with your map packs. now you should leave it alone.
Thanks node21.
I do have a question for you though. XBLA Unlocker had issues for me about unlocking some content. it would not unlock the "Optional Media Update" and only Yaris swap worked for it. Then the Left 4 Dead Map packs would not work with XBLA Unlocker or Yaris Swap but I was able to make it work with DLC Patcher made by Fatum and it worked fine. Does this have the issues XBLA had? I know that if you patch the content with yaris swap first for Left 4 Dead then if it doesnt work try DLC Patcher and it will be broken. You have to use 1 or the other. so basically if this scans my content and tries to unlock anything and it doesnt work all of my content it tried to unlock will be broken. Here is the explaination I got from Fatum as to why it breaks it:
Content lock is simple.
Example:
We have DLC for "GAME". This dlc contains national flags. There are 3..5..6..100 flags inside. Everyone download this same dlc but you are from Germany and you have unlocked your flag. Your friend is form Canada and he has Canadian flag why?
Your license: xxxxxxxxxxxxxxxx Content: 00000001
Friend license: yyyyyyyyyyyyyyyy Content 00000002
Other license: zzzzzzzzzzzzzzzz Content 00000010
File is this same only Content bitmask is different
If license is changed to FFFFFFFFFFFFFFFF (hex) bitmask is set to any console/profile (i think that this is set by last parameter: flag)
What do yaris swap?
Overwrite License to FFFFFFFFFFFFFFFF (very good;) and License to 00000001 (good for arcde and 80% of dlc)
What do dlc patcher?
If Content is different than 00000000 (ex 01000000) it's not touched but license is changed for FFFFFFFFFFFFFFFF.
If Content is 00000000 license is changed to FF.... and Contnet to 00000001.
That's all
If something is patched by yaris you can't patch it again because you don't know right content. Only forza dlcs have files connected with content mask. DLC Patcher was fast dirty app for Forza

dufc1983
You can manually fix files using hex editor
File 62138F85356E99BD8C62911766E4B7A13471133345 change 4 bytes at offset 0x234 (00000001) to 00020001
File 31DFB2848A16CDE4B0FB475BE7123B0FFFF0842145 change 4 bytes at offset 0x234 (00000001) to 00010001
Fatum worked with zouzzz and they rewrote Yaris swap to have better compatibility with this.