This dialog is used to build a new plot by selecting the columns from the tables available in the current project. First, select the table you want to use from the Worksheet combo box and click on New curve to create the curve. After that, select at least one column for X and one for Y using the <->X and <->Y buttons. You can also select columns for Z, X-errors and/or Y-errors using the buttons provided for these options. The plot will be created using the default style defined using the '2D Plots -> Curves' tab in the Preferences dialog.