This function is available now.
instead of adding a step at the bottom when creating a exercise, you add a round, then drag the steps in to the round and decide how many rounds you want.
just remember to ad a rest step at the end inside the round else it will be nonstop.
one problem with this is that in workout mode (watch), you only have the option to change the reps or the weight on the last set in the round, at least not with venu s2 series. This definitely is a bug that needs fixing.