http://bugs.winehq.org/show_bug.cgi?id=23993
--- Comment #1 from Dan Kegel dank@kegel.com 2010-08-13 23:56:22 --- You can substitute mono26 for dotnet20 and dotnet30 in that recipe. (Leaving out all of those makes the game decide to run its own dotnet30 installer.)
You also probably don't need gecko.