inserting grand pause, caesura, or "railroad tracks"

I'm a relatively new user. I have searched for a way to insert a pause in my score--what is commonly called "railroad tracks". So far, I can't find a way to do this. I can put a square fermata over a note, but I need to insert a pause with a square fermata over the pause. Has anyone found a way to do that in Notation Composer? I'm using version 2.6.1 on a Windows 7 PC.

Thanks