Search this forum or see the FAQ for tips on 'Merge'.[Link: remotecentral.com]
There is a printable PDF version of the FAQ available as well as the HTML version for which I have linked the 'Merge' topic above.
Most of what you need to get started can be found in an older ProntoEdit Manual. Here's the download link.[Link: files.remotecentral.com]
Also, I may have my editors mixed up. I remember Marantz's TouchScreenSetup has the RC5/6 dialog but not sure about ProntoEdit. If you need ability to create RC5/6 codes in a user-friendly way, for sure you can use TouchScreenSetup to create a device page with all your IR codes and then 'Merge' the small config file you have created in TSS with your own in ProntoEdit (PE).