To undertake something like this you really need to have a good understanding of the format of an IR signal. A good place to get started reading up on that is here...[Link: hifi-remote.com]
The next step is to contruct the raw Pronto hex. You can either do that by hand using the info gleamed from the previous web pages, or you can use a tool called Makehex
You said that your end goal was to build an actual CCF file. To do that, you would need to use ProntoEdit
. You would create the CCF using ProntoEdit and you would create the buttons that you need. You would then cut & paste the Pronto hex that you created into each of the buttons that you created.
Hey, I never said that it was easy! :)