It is easy to make double versions of single components.
Follow the instructions below:
Select the tool Double line or arc on the Line Drawing 1 tab and move it towards the line you want to turn into a double line.
Enter the Thickness (distance between the lines) in the input display.
Click the tool in position on the line, which you have chosen. Three lines appear. The light blue line is the original line which you want to turn into a double line. The red lines show where the inside and the outside of the double line can be.
Move the mouse pointer in the direction where the second line should appear. The line which is nearest to the mouse pointer turns into a solid line. Place the mouse pointer on the side you want and click.