Right click on the image and click print or just print page and bring the voucher with you.
Ok seems to be a problem printing this image our tech guys/gals are working on a solution and this will be fixed asap.. I found i could right click and view image then print it ok but we will endevour to get this fixed asap... For today only Thursday 25th June you can just turn up and say about the printing problem and you will still get the same deal :)