Display primary street as:

This option will display on the diagram itself the street names either on the N-S leg or the E-W leg of the diagram.  Intersection Magic does not know which street follows which direction.  The primary street is the first street that is selected when you created the diagram.  You have the option of having that street name placed on the bottom (E-W) or on the side (N-S).  The second street name will be placed on the other leg automatically.