Hi,
thank you for the kind words!
As for the XSL - you could update the source and add your own XSL but
you could simply stick to the XML structure expected - it is up to
you. I would suggest sticking to the xml structure proposed by the
plugin (it is documented), as for example get_xml only supports those
two outputs (flat & nested).
Of course - you could even copy the XML plugin, and make your own XML
plugin, this way you will ensure that it continues to work when I
update the core, just name it to something different.
Kindest regards,
Ivan