Creates a progress window, with given number of steps and identifier.
The window contains a progress bar that increments each time WM_ProgressWindowReport is called.
WM_ProgressWindowCreate <number steps> <identifier> [/title <window title>] [/caption <caption message>] [/message <progress message>]
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                             /caption  | 
                        
                             The caption of the window. This appears above the progress bar and cannot be changed after the window is created.  | 
                    
| 
                             /message  | 
                        
                             The status message of the progress window. This appears below the window and can be changed after the window is created.  | 
                    
| 
                             /title  | 
                        
                             The title of the window.  | 
                    
| 
                             number steps  | 
                        
                             The number of times WM_ProgressWindowReport has to be called to make the progress bar be completely full.  | 
                    
| 
                             identifier  | 
                        
                             The identifier that will be used to reference the progress window on update and close calls.  | 
                    
| ▲ Command Summary ▲ | ||
| ◄ WM_ProgressWindowCloseAll | WM_ProgressWindowReport ▶ | |