My first Puffy Shirt in Marvelous Designer

I've been practicing my shorts and shirt skills and experimented with the sleeves and a shirring effect at the back. I've done this with several internal lines and the elastic effect. CLO actually has a shirring option for lines on the outside of a pattern, and I compared the effect with the regular elastic. Turns out it was better for what I wanted to achieve (and MD doesn't have the shirring option).
I've made the thumbnails for various streams and videos in which I'm explaining how I did it.