Hallo Hraban

> How can I change color or dashing for only one or a few connections?

> Is it possible to set up some "classes" of cells that use the usual shapes
> but other colors or line styles?

Some time ago I had to make a presentation, wherein I had to solve the above
mentioned issues. At that time Hans gave me some tips. Though my example
file is in Dutch, I believe that this example can help you find your way.

Kind regards Willi