Cyclo ops calibration magnus

I have used my Cycle Ops for about 3 months now and the calibration is very annoying in Zwift.  Mentions are made of calibrating in Rouvy, but when I go to their page, I do not see a download for Mac, just Windows, iPad, iPhone, and Android  Also, I do not want to have to join and pay,  just to calibrate my trainer. Is the app free?

I figured out how to calibrate with out an app for my Mac.  I used the Android mobile app, BINGO, in 2 minutes on Rouvy, I was up and running, Hopefully, when I do a race today, the calibration will be accurate.