Yes, you do have to create the benchmark symbol just as P-F has instructed. Otherwise, they start deducting points which in turn affects your overall grade. If you look at the symbol it is just a circle with a vertical and a horizontal line through it with opposite quadrants hatched.
Shown below is one simple method for creating the symbol.
1. Create a circle and two lines (in proper orientation).
2. Move the lines using their midpoint to the centerpoint of the circle.
3. Hatch opposite quadrants using the "Pick points" button in the Hatch window.