The workouts are saved 'at trainer road' and follow your profile regardless of what you're using to control (phone, tablet, old mangled laptop with a non-functioning display) that's probably my biggest beef with zwift (apologies for the slight tangent). I haven't thought to try to create a video workout but I'll take a shot at lunch - even though I'm "really busy" right now ;)

edit - wonder if they could/would create workout templates like say "descending corkscrew" or "venture to the opposite perimeter"...

edit #2 - the sufferfest templates are still in the workout creator - for the time being (?)