I assume you have tried uninstalling and re-installing 8.64? Going back is fine, but since most are working fine (except the media settings for hot/cold press) seems logical to try and figure out what's amiss in your system. certainly troubleshooting is pita, and sometimes slow, but if you do so methodically you should be able to isolate the issue.
Does the job show up in your printing queue and just not print? Or does it not even make it into the queue?