In my Proc call, I've specified a right justification....but it does not appear that it is being applied in my output. Everything is still left justified. Is this a functionality that is not currently working in the tagset?
I downloaded JUST the ExcelXP tagset that was marked NEW March 2007 -- if that's the one that you downloaded and tested, then, yes, your best bet is to contact Tech Support.
(BTW, I had to manually drag the Excel columns wider to see the effect.)