First, “DARKLIGHT” not “Darknight”. http://community.wdc.com/t5/WD-TV-Live-Streaming-Discussions/Darklight-for-SMP-Beta-UPDATED-9-10-2012/td-p/407350
Second, the default theme uses the xml data the same way. The “default” moviesheet in Thumbgen is NOT used by the default theme (Mochi) because the default theme doesn’t require generating data with Thumbgen.
Mojo, Darklight and Mochi (the default theme) all use the metadata xml to display the metadata. As long as you generate the metadata xml for each movie the metadata will display.