To change the parameters for a button you should open the Configuration Dialog and highlight the button you want to configure. Then click on Button Properties in the Configuration Toolbar.
A button either accepts parameters or it doesn't. This is specified by the Allow Parameter Selection checkbox. If this is not checked then no parameters are configured for the button and when the CastleBar button is clicked it will immediately launch its target file or program
If Allow Parameter Selection is checked then when the CastleBar button is clicked it will not immediately launch its target file or program. Instead it will drop down a list of parameters for you to choose; when you select one of these parameters the target file or program is launched and the selected parameter is passed to the command.
You Add, Remove and Configure parameters in the same manner as you Add, Remove and Configure buttons. In fact the Configuration toolbars are almost identical.