Make sure that the signals you want to migrate are (well) learned in your Pronto, export the configuration as .ccf or .xcf (not .pcf) using PE. Import it into IrScrutinizer (Import -> Pronto Prof, or Pronto Classic).

There are also two command sets for Xfinity set top box at https://irdb.globalcache.com/ . Yes, they are XMP (XMP-1 to be exact). These command can easily be imported into IrScrutinizer with a few key clicks.

Many IR "learners" fail on XMP...