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Question # 32: How do I enable multiplayer hotseat campaign mode?
Answer #32:
1. First, copy your medieval2.preference.cfg file to your desktop.
2. Rename the copy of the medieval2.preference.cfg file to multiplayer.cfg.
3. Now, make sure that the multiplayer.cfg file is not read only (right click on the file, and check the properties).
4. Open this new multiplayer.cfg file with Notepad or Wordpad, then add this to what is already in the multiplayer.cfg file:
For Grand Campaign on V1.2 and later
[hotseat]
turns = 0
scroll = 0
autoresolve_battles = 0
disable_console = 0
disable_papal_elections = 0
save_prefs = 1
update_ai_camera = 0
validate_diplomacy = 1
[multiplayer]
playable = 1
5. Now save the multiplayer.cfg file and put it back on read only.
6. Move the multiplayer.cfg file into your C:\Program Files\SEGA\Medieval II Total War folder.
7. Now open up Notepad again. In an otherwise blank do***ent, type this:
medieval2.exe @multiplayer.cfg
8. Save the Notepad do***ent as Launch_Multiplayer.bat
9. Put this new Launch_Multiplayer.bat file in your C:\Program Files\SEGA\Medieval II Total War folder.
10. Now, if you want to, right click on the new .bat file and send it to the desktop (Create Shortcut).
11. When you want to play the multiplayer version of the game, double-click the .bat file. This will launch the game in multiplayer mode.
12. Once you are in the game, select Singleplayer. Then Grand Campaign.
13. Now, pick which factions you want to play. Just click on as many as you want. I am playing as all 17 playable factions now.
14. When you start the campaign, you will play each faction you have chosen in order. You can save and quit at any point and resume your game as you choose.
I found it here.>>>http://forums.totalwar.com/showthread.php/118-Frequently-Asked-Questions-amp-Game-Fixes/page2