Simple Command Editor

In the simple mode of the Command Editor (as shown above), the 
Function field is only a single line. In this mode you can 
specify the function (what the button actually does when you click it) in three 
different ways:
  - Using the drop-down attached to the field, you can select a pre-defined 
  command (as shown on the Commands 
  Tab in the Customize dialog). When you select a pre-defined command from 
  the drop-down, the function field will be populated with the underlying Opus 
  internal command and arguments. For example, selecting Viewer Pane 
  from the drop-down will fill the field in with Set 
  VIEWPANE=Toggle as shown above. 
  
- You can directly enter the name of an Opus internal command, with its optional 
  arguments. 
  
- You can select an external program to run using the Browse button ( ). You can append 
  various external control 
  codes to the external program's command line in order to pass filenames 
  of selected files to the program. ). You can append 
  various external control 
  codes to the external program's command line in order to pass filenames 
  of selected files to the program.
  
 This 
  would launch Notepad, passing it the name of the first 
  selected file in the file display.
 
When you select an external program to run, the Start in and 
Run fields will be enabled.
  - Start in: When a command runs an external program, this 
  field specifies the folder that the program will start in (in other word's, 
  the new program's current directory). 
  
- Run: When running an external program this lets you 
  specify how the program's window is to appear. You can choose from Normal 
  Window (the program itself defines the window size), Minimized 
  (the program will open minimized to the taskbar), Maximized (it 
  will open full screen) and Hidden (it won't show a window at all). 
  Not all programs will respect these settings. You need to be careful when 
  using Hidden as it can result in the program running without any 
  visible user interface - you should only use it when you know that's 
  definitely what you want. It's most useful when launching a DOS script that 
  runs and quickly exits, as it lets you hide the quick "flash" of the DOS 
  command prompt. 
 
Click the Advanced button to switch to advanced mode.