Hi, Has anyone used a HP design Jet 4520 plotter? I'm using a Mac Pro and a 2011 MacBook Pro 17" and I can't get this plotter to work on either. HP Drivers are pre-installed for Snow Leopard. I have not been able to get this plotter to recognize tif, PS or jpg files. Computer can see the plotter, I have input the correct paper dimemsions, and when I press print, it will pause and not print out. If anyone has experience with this plotter would you be able to identify what step I'm missing to get this very large paperweight working? The ocal service provider for HP where I work was able to get it to work on a windows computer but not on my Macs. HP's web site was no help at all. Ilook forward to any response.