In this place you can customize text on proforma. You can also set numeration format and enter some messages displayed only on proforma.
Numeration rules are the same like for regular invoice. You can choose from three patterns of numeration:
Proforma can by easli converted to invoice. Just select your proforma on list and clik right mouse button to show hidden menu. Select Convert to Invoice option. It will open invoice details dialog with new invoice but with items and totals based on selected proforma.