you have to provide a server, where the updates can be found (in the easiest way this is a simple http or ftp-server). the game have to
- establish a connection
- calculate the differences (the easiest is to use a versionnumber)
- download the models and maps

if you do this, you should add some security like 2-sided authentification using hashes or something

if you want to update your scripts too you have to write another application. this is afair not possible with acknex, because the engine wonŽt start if any of the scriptfiles are modified. so you have to update your game-exe too if you want to update your scripts. so youŽll need an external game-updater. otherwise you cant copy the new game-exe on its place