I think every release of Outlook had at least one printing bug slip though the beta testing phase because so few people print calendars and Outlook 2013 kept up the tradition. This time around, the bug is with the Calendar details style: Appointments are duplicated in the print out.
This problem was fixed in one of the July 2013 updates. Verify Office is updated from File, Office Account, Update Options. You should have version 15.0.4535.1511 or higher.
The Calendar Printing Assistant for Outlook should work with 32-bit Outlook 2013 if all updates are installed.