This is SkywingvL's description of the CE:
"The NWN2 Client Extension is an add-on to the standard NWN2 game client that restores multiplayer server browser functionality (including listing of servers hosted in the game client if the host is using the Client Extension), and brings a wealth of multiplayer-oriented feature improvements and fixes for game client bugs that are designed to improve the gameplay experience for both players and DMs.
Highlights include the ability to list online game servers and PWs in-game, chat improvements including copy and paste support, an improved minimap display, numerous "power user" features for DMs using the DM client, hotbar macros for queuing up multiple buff spellcasts in one button press, and more. Extensive documentation is provided with the included readme file. Simply extract the Client Extension zip file to a folder of your choice, and use the included NWLauncher.exe to launch the game client to take advantage of the NWN2 Client Extension's added features and bugfixes.
The Client Extension also includes seamless auto-update functionality to keep the CE current with the latest bugfixes and improvements. "