Well, “Multi Selection” is for doing multiple selections.
Just Ctrl+LeftClick will do maybe nothing, depending perhaps on the setting. (don’t know)
For me Ctrl+LeftClick will select a whole word.
Ctrl+LeftClick again, or Ctrl+Selection will select additional portions of text. That what it is for.
Have you enabled Multi Selections? > Tools Customize > Edit
I don’t know what you expect should happen?
Maybe take a look (It’s not easy to find anymore on the new forum, but with G00gle it is findable):
New in Version 13: Multiple Selection Editing
http://www.emeditor.com/text-editor-features/history/new-in-version-13/
Upcoming new feature: Enhanced Multiple Selections
http://www.emeditor.com/tag/v13-1/