To do this, you need to make a build of the component using the trunk version of Perian with Xcode. Then copy the component to /Library/Quicktime. The only one problem is that the fonts are quite small for a big TV… Maybe the pagecodes are differents on the Macosx & AppleTV…
Just copy Helvetica font onto the apple tv.
I copied Helv* from my mac’s /Library/Fonts/ dir. to the same dir on the apple tv. Rebooted and the font problem was fixed.