This is yet another chord exercise.
Press 'New chord' to begin.
Identify the chord type by clicking on the buttons on the left part of the screen.
Then, try to find out the order of the tones in the chord, from bottom to top.
If you stack the tones the wrong way, the program will tell you so. And then you have to click on the button labeled '<<<' and try to stack the tones again.
On the top the the config page there is a frame labeled Lesson file, that selects what lessonfile to use. This frame is the same on all exercises that use lessonfiles. There are two combo boxes. The one on the let you select what collection of lession files to use. The collection 'solfege' contains the files distributed with the program. The 'user' collection is files created by you, by default located in $HOME/lesson-files. It is possible to define other collecitons by editing $HOME/.solfegerc2.0.