I would wait at least a day before emailing the author - maybe someone here at the Monastery will figure it out. If and when you do email the author, be very consise and polite (you know this ;)). Matts has written many XML modules and perhaps he has used this one before, you might want to /msg him and invite him to look at your question. mirod is another XML Wizard, he may have an alternative for you.

Another outlet is http://rt.cpan.org - if this is a bug, you can report it to the author at http://rt.cpan.org/NoAuth/ReportBug.html?Queue=XML-Generator-PerlData

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)