You should press on the  icon to open the Options window.

In the Excel Import dialog, you can import a luminaire list in the form of an Excel table. 

To do this, it is necessary to select the Excel file and specify the worksheet and rows/columns in which the data is located. 

Alongside the x-coordinates, it is also possible to import the control groups. The Preview section on the right shows which data is being adopted. 

You should then press the Assume data button to import the data into the program.

Options window and Excel Import dialog