FAQ

Europa Universalis IV 1.3.1 Hotfix - 3DM - All updates and DLC included
http://pan.baidu.com/s/1zN4fi

Note: Original link provided by 3DM. Anon doesn't take any responsibility for the contents. Use at your own risk. steam api fires for virus still, use RVTFIX steam api. Always use an antivirus.

Activating the DLC
Make sure you Europa Universalis IV folder is NOT read-only. Use 1.2.2 update (not the DLCFIX one) then using a fake steam account, login to steam and run the game (making SURE your cache is clean because there is a dlc_signature file there). After that apply the 3DM update. You don't need to run steam anymore after the DLCs are activated.

The original 1.3.1 3DM update fires for virus, just use RVTFIX steam api. It is the 3DM update with the RVTFIX steam api.
No release with the right checksum has been found as of 05/11/2013.

Q: Did anyone manage to activate the DLCs?
A: Yes.

Q: I did all the above steps and the DLC still don't work!
A: There's a lot of answers to that:
1.Make sure the DLCs are working before applying the 1.3 update.
2.Repeat the above steps more than once.
3.Clean cache, run the game without the DLC the first time, exit, open steam with the fake account, now run the game with the DLC activated. See if it's working.
4.Use one of the steam api that comes with 1.2.2 DLCFIX or 1.3. They fire for virus, so use at your own risk.
That's the known fixes. Try all of them and don't complain in the threads. Yes, we managed to pirate the DLC.

Q: Where/what is the RVTFIX?
A: http://thepiratebay.sx/torrent/8977062/Europa_Universalis_IV_-_MP_Patch_[RTVFiX]_[Proper]

Q: How to play online if I pirated the game?
A: http://www.tunngle.net/wiki/Network:Europa_Universalis_IV