For those of you who play and love Medieval II Total War the way I do, you absolutely MUST check the following link out:
http://www.forkingorcountry.com/This is a new mod that was finished in REMARKABLE time considering how much work the modders put into it. It brings Medieval up a hundred years into the age of Pike and Shot and has a full campaign covering the English Civil War. It's the closest thing to a 30 Years War mod for Medieval II that you're likely to get, so I'd try it out. The battles run very well and feel very different from the vanilla game, very pleasing.
Rejoice in the Lord! Death to King Charles! On for Old Ironsides!