How can I use copmosite cable on older TV?

artisticcheese you have posted in the wrong forum.  (This forum is for the Old Wdtv Live / Live Plus)

You have a “WDTV Live Streaming”  (Note the Pictures at the top of the page)

http://community.wd.com/t5/WD-TV-Live-Streaming/bd-p/streaming_discussions

And No, the WDTV Live Streaming does not Support “Component” Video … only “Composite” (480i,576i) or HDMI (up to 1080p)

See Tony’s answer here:

http://community.wd.com/t5/WD-TV-Live-Streaming/New-WD-TV-Live-output-to-Composite/td-p/630721