You cannot use cWindow directly, it is only a base class from which all windows are inherited. You need to use cLuaWindow. Note that it inherits all cWindow's functions.
For a simple example on showing windows as reactions to commands, see the Debuggers plugin (distributed as built-in with MCServer / https://code.google.com/p/mc-server/sour...uggers.lua ), it has a "/testwnd" command that shows a window filled with custom items and has some processing when the window is closed. You can safely ignore the GCOnTick-related stuff, that's only for internal testing purposes.
In case you are wondering why it is so, why two classes, here's the explanation: It is planned that we'll add a hook that will fire each time a window is opened, closed, or clicked. But MCServer uses different classes than cLuaWindow, so it wouldn't have a cLuaWindow instance to hand to that hook. Instead, we chose to have a common ancestor for all windows, so that all windows can be manipulated the same way. That's the cWindow class.
For a simple example on showing windows as reactions to commands, see the Debuggers plugin (distributed as built-in with MCServer / https://code.google.com/p/mc-server/sour...uggers.lua ), it has a "/testwnd" command that shows a window filled with custom items and has some processing when the window is closed. You can safely ignore the GCOnTick-related stuff, that's only for internal testing purposes.
In case you are wondering why it is so, why two classes, here's the explanation: It is planned that we'll add a hook that will fire each time a window is opened, closed, or clicked. But MCServer uses different classes than cLuaWindow, so it wouldn't have a cLuaWindow instance to hand to that hook. Instead, we chose to have a common ancestor for all windows, so that all windows can be manipulated the same way. That's the cWindow class.