You need to modify the Fiery PPD file at the following line in order to ignore the CUPS filtering process which is not needed since the Fiery is already a postscript printer. This problem also occurs with Quark 7.0
before
cupsFilter: "application/vnd.cups-postscript 0 /Library/Printers/Canon/PS3/Filters/fierycupsfilter"
after
% cupsFilter: "application/vnd.cups-postscript 0 /Library/Printers/Canon/PS3/Filters/fierycupsfilter"