Via Chrome or Firefox, you’ll need to download and install the web extension so when you go to the SYSTM web app, it allows you to download the FIT file for the indoor or outdoor version of the workout. Once downloaded, you email it to workouts@rgtcycling.com then it magically appears in RGT as one of your uploaded workouts.
Here is the link from the forum that explains the process
And here is another place with some detail about creating an event and using your workout
https://wahoox.forum.wahoofitness.com/t/magic-roads-not-building/20697/6?u=glen.coutts
If you’re totally new to RGT, I’d suggest 2 things. 1, go to wahoo support site and review some of the stuff. A lot of it is NOT intuitive. https://support.wahoofitness.com/hc/en-us/sections/4549315382162-RGT and
2, If you’re on FB there’s a great and super helpful group of volunteers in the RGT Users Support Group