You're zipping from the wrong starting point. There shouldn't be a sthf directory in the zip. The manifest should be at the root of the zip and there should be subdirectories for source, images, and artwork. There's a whole lot in the zip that doesn't need to be there (all the __MACOSX stuff, Makefile.xml, .DS_Store, etc.).
By the way, I tried to play a video and my box rebooted.
-JT
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