Global Mapper v25.0

Exporting to Terragen

I've seen mention in various spots that I can export data from Global Mapper into a .ter (Terragen) file.
I was hoping someone could provide me with a basic step by step on how / where to do that?

I'm importing contour data in a Shape file.
Are there steps I need to do to prep the data to be able to see the Terragen export option?

Any help would be greatly appreciated.