Allows you to define a new symbol that will be available for inclusion in the markup layer.
Symbol preview - Displays the element you selected from the active markup layer.
Symbol description - Enter a brief description for the new symbol. You can use this description to help find the symbol again later.
Symbol file - Displays the location and name of the symbol file in which the new symbol is stored. To select a different file, enter the path and name in this field, or click the Browse button and find another file.