CDL (Circuit Description Language) is almost identical to Spice format, and is used as a netlist interchange method. CDL options are controlled with the CDL Preferences (in menu File / Preferences..., "I/O" section, "CDL" tab).

This dialog controls the library name and path information that is written when generating a netlist. You can specify an Include file which will be inserted at the top of the netlist. Also, you can choose to convert square-bracket characters (if your CDL cannot handle indexed signal names).