Adding nodes to or deleting nodes from existing shapes in SCAL4

Have you had a hard time adding nodes to existing shapes in Sure Cuts a Lot. I'm not surprised because it is a bit tricky, but in this video, I show you how to add and delete nodes and why it doesn't seem to be working, which is what I thought at first.

Plus symbol lets you add a node

 

 

 

Minus symbol lets you delete a node