It depends what you want the CCF file for.

For almost all models of Pronto, you could use ProntoEdit, go to the properties of some button and paste in one of the short Pronto Hex strings quoted in this thread.

But most non Pronto programs that understand Pronto Hex and/or CCF files, won't understand that version of Pronto Hex. For those, you would need to use MakeHex and nec1.irp to generate the longer form of Pronto Hex from some of the numbers in the short form.