The downloadable version has four and their names appear on the opening screen.
They are located in the JIMScenarios folder which is located in the JIM folder.



Each folder contains the seven files that JIM needs for setting the parameters


So you can make a folder for a new scenario, and copy the files from that mod into it.
It will then appear for selection when you run JIM.
Of course this does not install the new scenario for flying in EAW 1.28C. It just allows you to set the mission parameters for it using JIM.

Jel