Ok, after a lot of work, I've finally got almost everything working. However, at this point, when I attempt to send XML for a roster change via PUT, I get this error:

<description>Invalid XML PUT. Error at line 2 of input XML.</description>\n <detail/>\n</error>\n

My XML is as follows:

<?xml version='1.0' encoding='UTF-8'?>\n<fantasy_content><roster><coverage_type>date</coverage_type><date>2012-11-29</date><players><player><playerkey>304.p.3173</playerkey><position>PF</position></player><player><playerkey>304.p.4612</playerkey><position>PG</position></player></players></roster></fantasy_content>

I'm sending to this URL: http://fantasysports.yahooapis.com/fantasy/v2/team/304.l.41835.t.12/roster/ I've pulled the XML and the URL from what the library I'm using reports, so I'm pretty sure that those are exactly what are being sent. I'd appreciate any help. Thanks, Matt