Get it at
http://users.tpgi.com.au/jfwfreo/walls.zip
Notable changes to this version:
Corrected an issue to do with people who have low graphical settings
Now has an installer
Loads separately from the game via a seperate desktop shortcut
Supports multiple languages now
But the best part is that (thanks to a Big Ugly Hack) the AI will now attack walls instead of just ignoring them (install the mod, start the game, wall in your construction yard and wait and the AI will blow up your walls to win the game)
Naturally once 1.07 and the SDK comes out, the walls mod can be done as a proper mod that can load into the game via the official mod swap tool etc