Play as the Joker (PC)

Play as the Joker DLC for Batman: Arkham Asylum (PC)
Originally a PS3 exclusive, the Play as the Joker DLC pack adds extra challenge maps where you play as the Joker.
WARNING: Only compatible with original version, GOTY Edition not supported!

Instructions:
0. UnRAR.
1. On your PC, navigate to My Documents -> Eidos (or Square Enix) -> Batman Arkham Asylum -> BmGame -> Config. Delete BmGame.ini (if it exists). It will be replaced later.
2. Navigate to your game's installation folder. Something like C:Program FilesEidosBatman Arkham Asylum or C:Program Files (x86)Steamsteamappscommonbatman arkham asylum
3. Copy the BmGame folder to your game installation folder. The folders should merge, and it will ask if you want to replace some files. You do.
4. Navigate to BmGame -> Config and find the file DefaultGame.ini. Open it up in a text editor.
5. Open the DefaultGame.ini from the RAR in a text editor.
6. We now have two version of the DefaultGame.ini file open. In the RAR-version, find the line that says "TLJF 26-Jul-2011 Added DLC content", about 60 lines from the bottom. Copy ALL of the text from that point down (about 60 lines), ending with "DLCJokerPlayable=true", to your clipboard.
7. Paste those 60 lines into the other open copy of DefaultGame.ini, at the very end of the file, after the last line.
8. Save your version of DefaultGame.ini. Close the other one.
9. Start Batman: Arkham Asylum. A new BmGame.ini file will be created. Note: The game may freeze the first time you try to start it. If this happens, give it a minute, then force quit and try again. It worked for me the second time, and I haven't had any problems since.
10. You game should now have the Joker challenge maps added under the "Challenge Maps" menu option, and all DLC will be available under the "Downloadable Content" menu option.