Printing a 4 by 6 inch photo?

Print them to PDF until you get the layout situation taken care of. Then you can print straight from the PDF 'cause you know exactly how it's going to come out of the printer. As for your formatting issue, can you do something like print upside down? I know it sounds silly, but I've had to do that in other programs to get the top and bottom margins correct. Make sure to turn off any auto-resizing functions as they generally lead to broken printers because of 'unfortunate baseball bat accidents'.