DLC MODDING:

For DLC modding to work properly, you need to place the two supplied dll files in your Mass Effect 3 Binaries/Win32 directory.  Binkw32.dll replaces the game's existing dll of that name and it refers to the second dll, Binkw23.dll and allows any DLC mods to get through the game startup DLC integrity check.  If you do not replace the original Binkw32.dll and add the new Binkw23.dll file, the DLC that was modded will fail the startup integrity check and anything in that DLC will be unavailable to you in game, this will also cause you to be unable to load certain save games you may have that use the DLC you've modded.  

Best course of action after modifying DLC is to run the DLC TOCbin Updater under "Developer Tools" and the "TOC" submenu.  Select "File" and then select "Check and Rebuild SFAR".  Navigate to the DLC folder of the DLC you just modded and select its "Default.sfar" file.  That's it.  The updater will check the files in the DLC and rebuild the PCConsoleTOC.bin file for the DLC.  This action will prevent (or correct) DLC load/run errors >90% of the time.

If you want to back out any DLC mod you go to Origin, right-click on your game and select "View Game Details".  This will open up a window with all your DLC listed.  Right click on the modded DLC and then select "repair".  Origin will convert that DLC back to unaltered plain vanilla.