More complicated sections will typically involve more than one shape. These are referred to as 'built-up' sections. To create a built-up section, you simply need to add all the shapes that make up the section, adjust their dimensions, and then perform operations (translation, rotation, mirroring) until they are in the correct position.
In this example, we're going go create a section made up of two channels which are back to back of each other. We'll be using the standard metric channels in this example.
1) Start by adding your first channel from the 'Templates' menu. Select 'channel' from the menu and click 'Add'.
2) We want one of the channels to be facing left, so let's mirror this channel vertically. Under the 'Mirror via Y axis' heading, click 'True'. Note that a similar effect could have been achieved by instead rotating the channel 180 degrees.
3) Since we want to align both channels against the vertical Y axis, we need to translate the channel left by a certain distance. To determine by how much, hover over the bottom right point with your mouse. Notice that the coordinates are (45.78, 0). Since we want this point to sit flush with the Y axis, we simply need to translate everything by -45.78 mm (i.e. to the left).
4) Before you try to add a second channel, make sure that the 'Clear Others' checkbox is unticked. If not, then your second channel will erase the first channel.
5) Go back to the 'Templates' menu and add a second channel. You should now have two channels which are sitting flush against each other, side by side.