In a .idw, create text, in the dialog box there is a menu titled "Type". From this menu, select either model or drawing properties. In the menu titled "property", select "File name and path", then press the FX (function) button. This will add the property <filename and path> to your text.
This can be used in a sketched symbol or title block and then saved to your template so that you do not need to recreate this every time you start a new drawing.
David