Press the Insert button, the Insert Strings dialog box will be displayed.
The string name can be entered in the first field.
To add points to the string, click on the points. To specify a centre point, click the cursor into the 'Centre Pt' field and then click on the centre point, or, type 'C' on the keyboard and then click on the centre point, or, type Cnn in the 'Pt B' field.
Use the Undo Segment button to delete the last line segment. You can delete segment repeatedly until you reach the beginning of the string.
To enter a sequence of points into the string tick the 'Pts To' box, then click on the terminating point. This will insert each consecutive point number between point A and point B