There is a bug that currently prevents the menu from working as desired. The work around is to open “Help > Welcome Quick Start” and create the GPS Watch example model. Once the model is created, you will see it contains a “Shared EEs” package. You can either copy and paste the entire package or a specific EE to your own model.
The next version of xtUML Editor will have a fixed “Add EEs” menu as well as contain additional enhancements that allow xtUML Execute to pull EE implementations from a jar file like it currently does with realized components.