The buttons at the bottom of the 
               Work with Classes window are: 
               
            
 
            
            
               
               - Refresh – Refreshes the information listed in the grid. 
                  
               
- Delete – Deletes the Changer Program for the selected class. 
                  
               
- OK – Saves any changes that have not been applied and closes the window. 
                  
               
- Cancel – Cancels any changes applied to the selected class. Any actions confirmed with the Apply button cannot be restored with
                  Cancel but must be entered and confirmed again. 
                  
               
- Apply – Confirms the changes made to the Changer Program of the selected class.