Aloha miriam,
That exercise is for you. Do it when it is show to you like that, but it's not one to share with others. It was put out there for your situatuation.
As for the solar plexus area. That is worked in a lot of differnt exercises: moving of Y&Y, Harmony of the Universe, 7 steps, and the small universe. You may be thinking of looking at the energy areaso of the body in terrms of chackras or another perspective. In Sping Forest, Chunyi doesn't look at it that way. Not that it's not valid. He'll talk about a lot of different systems and modalities which look at how the energy sytems work. His is more based in tradition CHinese medicine, so he's looking at meridian channels and Dantians. When he comes to the heart area in the Small Universe, it's the middle Dantian, solr plexus (chakras and otherwise), the heart, wan tang, etc., rather than a pinpoint spot, a chakra, or jus the heart organ.
It's the same in the Moving of Yin & Yang. SO many things happening there that you may or may not hear him talk about even at a Level IV class, but it's still happening.
Much Love, Shawn