Order matters - here's the wiki page about things:
http://hlkitwiki.wolflair.com/index...._Element_(Data) So there, you'll see that the order of the elements (for the ones you've got in your file) is fieldval, usesource, tag, but on line 14, you've got a usesource, and then a field, so once it finds "usesource" it figures all the categories that are supposed to come before that have been skipped, so fieldval is not on the list of things that can come next.