9/8/2015 Updated Bluehost PHP to 5.4, and Cantata stopped working. Evidentally the root cause was that there was a pass-by-reference (&#cssNum) in index.php, and the solution was to just remove the & because it is deprecated and no longer needed.

The BlueHost error log:

[08-Sep-2015 10:37:49 America/Denver] PHP Fatal error: Call-time pass-by-reference has been removed in /home1/quizkidn/public_html/cantata/index.php on line 601

I also had received a “bad header” error, which I fixed by removing an extra copy of php.ini that I added to the cantata subdirectory when attempting to fix the problem.