To model elements, you must first add at least one material and one section to the project from the materials- and section database. To add a material from the database, do the following:
Click in any cell from the Input Workbook to activate the contextual ribbon
Select 'Materials' from the 'Active Sheet' dropdown menu in the contextual ribbon
Click on 'Open DB' to open the material database
Notice the 'Open DB' button text now changed to 'Add', now select a material by selecting any cell from the material database on the 'Material Database' panel