While not what I would consider an "expert" on IR codes, I am aware that there are many standards and they are generally based on what is known as an executor (base of some sort).
We had recent occassion to have one of the all in one type companies learn some codes for a piece of equipment only to find that the mfr had created an unknown executor, requiring teh company to create the new executor to provide compatability to our equipment...major time/pain.
On a positive note, most products are some derivative of existing executors and are available on the all in one products by using what are known as "extended" or "magic" codes. This simply makes the remote create a code based upon an X/Y lookup from an internal code table.
For those looking for codes, have you checked with the "other" guys to see if their remotes can so the codes, because if they can, Pronto should be able to learn them also.