Just launch RPM2, click on Radio, click on Feature Data. Read it out of the radio, make a note of where the .fss file saves to. That file gets sent out to your dealer or direct to the Harris TAC, along with your feature order. A new version comes back to you that you then load into the radio. Simpler than it was in the legacy radios.
The .fss file is plain text, mostly, showing what option codes are in the radio, but there is a section that consists of encrypted data so you can't just easily add features by adding lines and option codes.