I'm probably way behind the "curve", in a manner of speaking. Since I posted this question I've been in touch with Roy and finally arrived at the conclusion that with Mavericks I have to print in 2880 resolution only. I had been trying to use the 1440Super, but it simply would not print at all. The " 'Filter' failed " error kept popping up and that's as far as I got with any res other than 2880. I assume there are others who have found this to be the case as well, but if some of you folks have found differently please advise. Not sure which OS was the first to stop allowing QTR to print with the lower res settings, but I'd be interested in finding that information.