Here you'll be able to configure Knights to use various "Chess Engines", which are computer opponents you can play chess against. These engines are separate programs that do not come with Knights. To use them, you must first download a chess engine. Tim Mann's Chess Engines page has a great list of available engines for you to download. Knights should work with all of these. See the README and INSTALL instructions that come with each engine to install it.
Once you have a chess engine installed, click the Add... button on the right hand side of the window. A new window will be displayed.
The only things that you MUST enter to use the engine are the Protocol and the Engine Filename.
Engine Name is what Knights will call this engine when you select it as an opponent, or if there is an error. This is set for you if you leave it blank.
Protocol is a list of "languages" that computer opponents can speak. Knights acts like a translator by taking what the engine says and converting it into a move on the virtual chessboard. It is important to have the correct protocol or else the engine won't be able to play.
For most engines, you should select XBoard as the protocol. The Knights protocol is reserved for future engines to use.
Engine Filename should contain the actual location of the engine on your filesystem. Include the full path, unless the engine is in the search path. If you don't want to type this in, you can browse your filesystem with the folder icon on the right. Simply find the engine, left click on it, and left click Open.
Command Line Arguments is where you should add any special options for this engine. See the engine's documentation for a list of options and their useage.
Log File is a special text document which records the "conversation" between Knights and the engine. This is very useful for engine developers and for users who are having trouble getting Knights to work with a particular engine. Most users can leave this blank.
Click OK and Knights is now ready to use this engine!
You'll notice options which enable "Book Engines". Book engines are a kind of helper for the computer opponent. These types of engines are new and experimental. Therefore, you should not enable these unless you are a chess engine developer or unless you're sure that the engine supports "Bookengine" mode ( XBoard version 3 and Knights protocols ).