A simple workaround: Upload the file to Google Docs (now Google Drive) and you can view/print from there or download to a .pdf file! Simple.
I found a suggestion on dogpile.com search that suggested opening the .XPS file in a google email account and opening it with "viewer" instead of downloading it. Once in viewer, click the print document icon in the upper window tool bar and it can be downloaded as a PDF file to your Mac at that point. It worked for me but I was only opening a 4 page file.