Yes - I downloaded it the day it was available so I would have time to play with it. I have done 2 practice runs with it, including my 22 miler 10 days ago.
If you launch the app go to the "Tracker" screen (has 'My Claimed Profile" at the top). The option to go to that screen is at the bottom of the app page (along with Map, Leaders, Info an Messages). Once on the Tracker screen, Tap on the area with your claimed profile at the top (should have your name, Marathon and Real-Time Remote Racing. When you tap on that it should take you to the screen with the green start button for the Practice Race.
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