More than a few folks posting on a regular basis who may chime in with different takes, but I’ve found that the setup of new workouts on the ErgData (C2’s app) or ErgZone (3rd party for a range of rowing machines) apps to go rather quickly and easily. And since many of the Athletica workouts rhyme, I can later edit an existing workout for any particular session.
Both apps will send the workout to the machine (PM5-only wirelessly, PM4 with a cable), though I find the phone offers a clearer presentation of the current and next steps in the workout.
Beyond that, if your experience is anything like mine, I imagine you’ll find that platform uniquely applicable to a rower’s development and as uniquely supportive of and adaptable to that rower’s progress.