It’s not quite “intuitive” but there is some sense to it. In your first message you said you had a problem with the FIT file. It’s possible the FIT file you created was from a buggy GPX file. Have you tried another? Did you download it from Strava? Did you run it through GPX Magic before emailing to RGT?
In your second message you said you found the workout. Assuming it is okay. But, if you want to fiddle with targets, you’ll need to create another FIT file and send it to RGT.
As to the question on targets, you change the targets in the FIT file using the exporter extension:
See screen pics from Chrome:
When I am on the SYSTM web app (see URL), in the top right corner, I’ve made the FIT Exporter Extension visible. It’s the blue X.
When you click on the Blue X, there are options for settings. You’ll see I set mine as Target Value plus 0%. That will give you the exact target as set in SYSTM so if SYSTM calls for 200 Watts, the workout in RGT will call for 200 Watts:
You can change the value up or down by clicking in the box or using the little up/down triangles that appear when you are in there. Here is one going down 15% (which of course you’d NEVER do )
Here is one going up:
To find the workout you created using your FIT file when you are creating a Group Ride event, you do that at the RGT website here are the visual steps:
First click Create Event
Then choose to Create a Group Ride
I chose the Magic Road that I created from a Sunday Road Ride but had to scroll the list to get it
Once I found MY Magic Road, I select it:
RGT Then show you the Event you are about to create and if you look down that page, you see the option to ADD a Workout. Click that:
Tap the UPLOADED Tab to find the workouts you’ve created from FIT Files and select the one you want to use:
In my case I chose Sub- Threshold with Surges 4x12:
Once selected, you’ll see the workout has been added to the event
There are other options to play with too, like how many laps, adding BOTS, real or pacing etc that you can fiddle with too. I messed up on my bot selection for my ride as the 5 I picked all finished well ahead of me and I did my workout all “alone”.