and what server web address do you use in the watchtv setting, where are you pointing it for the xml files?
And for testing use my server http://ps3hax.net23.net/
in the settings of watchtv, then I'll edit my xml to see if the feed works, then you can have a copy of my xml and server it yourself after.
if your not doing it already run MM and then start showtime then run the watchtv plugin. Can you do it that way if not already as I believe its the best way.