Hi Andy
Sorry for the delay. I went on vacation as the next Roastmaster update was in review with Apple. It's live as of about 10 minutes ago.

To enter temperature readings from a thermometer or probe, you'll need to create a Reading curve. In a new roast, tap the blue button near the roasting gauge, and tap "New Curve". Set it to Reading, and the appropriate measurement system (C or F), and save. Then, back in the roasting console, make sure that new curve is selected (tap the graph to toggle through each curve in the roast).
As the roast is in progress, all you need to do to enter temps is tap the digital readout near the gauge, and enter the temp. It will create a timestamped node at that temp. You can define as many curves as you need for recording temps.
Once you hit on a good one you want to match for future roasts, you can copy and paste it from the roast to a new profile or program as a target to match in future roasts. Whenever you select that profile or program in a roast, the target curve will be visible in the roast as well as any new curves you define in that roast for recording new temps.
Hope this helps. Let me know if you have any other questions.