I've done exactly what are seeking, but using the printer as a serial device and sending down the correct codes. Doing this I create a label with a barcode and many lines of text. The printer I used was a Zebra ZQ500. The printer is able to usually work in 2 ways, 1 where the text you send it printed, great for plain text, but you then don't get access to the many printer features. For this you put the printer into another mode, where it is expecting ZPL commands. I imagine your printer has similar features. Happy to share some code if this is of interest, but you will first need to see what command language your printer supports.
Colin