addToPanel(mainPanel, editConstraints, 1, 2, separator = new JTextField(20));
addToPanel(mainPanel, labelConstraints, 0, 3, new JLabel("Skip initial lines: ", JLabel.RIGHT));
skipLines = new JTextField(20);
Color lightRed = new Color(255, 202, 197);
skipLines.setInputVerifier(new IntegerInputVerifier(0, Integer.MAX_VALUE, skipLines.getBackground(), lightRed));
skipLines.setToolTipText("Number of initial lines of input to skip. Must be an integer >= 0.");
addToPanel(mainPanel, editConstraints, 1, 3, skipLines);
addToPanel(mainPanel, labelConstraints, 0, 4, new JLabel("Store variables also in System Properties: ", JLabel.RIGHT));
addToPanel(mainPanel, editConstraints, 1, 4, storeSysProp = new JCheckBox());