In order to play karaoke you have to have corresponding .kas file in your directory. You can either create one (see How do I create my own Karaoke?) or get one form Evil Laboratories website. You can check if .kas file for you song is available either by pressing ?Get karaoke? button in EvilLyrics while playing the song or by searching or browsing the archive at our site.
If particular file is available, is will display on our site as some weird selected text. Just check whether it is timestamp file for the song you are playing (song and the length fits) and drag and drop selected text in EvilLyrics window. It will be saved into .kas files in your lyrics directory and next time you play the song, lyrics will be highlighted.