About open form buttons 
An open form button lets users click a button to open a FirstClass form without a body that can contain formatted text (such as the Preferences form). 
Open form button when drawn: 
Open form button when complete: 
 
  
Adding open form buttons 
1       Choose Fields > Buttons & Groups > Open Form Button. 
2       Add this field to the form. 
3       Update the following fields on the Contents tab of the Field Attributes form as required: 
 
Text  | 
The button name.  | 
 
Form ID  | 
The form ID of the form you want this button to open.  | 
 
Default button  | 
Makes this button the default action when the user presses Enter/Return. Selecting this also turns on the "Border" attribute.  | 
 
Icon ID  | 
The resource ID of an icon that you want to add to the button. If the button contains both text and an icon, the text is below the icon.  | 
 
  
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