[Plugin : wp web Scraper] Need a Quick help

Hello,

I need to use a wordpress plugins : http://wordpress.org/extend/plugins/wp-web-scrapper WP Web Scraper to extract the link of an audio tracks on a itunes web page.

here’s the page where i want to extract the link :

http://itunes.apple.com/us/album/guero/id52311104

here’s the link I want to extract on this page :

[audio src="http://a1.phobos.apple.com/us/r1000/033/Music/d2/3d/ac/mzm.pdxkvtef.aac.p.m4a" /]

And here’s the part of the code i want to scrape :

<tbody> <tr metrics-loc="Track_" adam-id="52311106" audio-preview-url="http://a1.phobos.apple.com/us/r1000/045/Music/b0/74/15/mzm.xueigfme.aac.p.m4a" preview-album="Guero" preview-artist="Beck" class="song music" preview-title="E-Pro" preview-duration="30000" row-number="0">

So in my post I have the following code :

[wpws url="http://itunes.apple.com/us/album/guero/id52311104" selector="@audio-preview-url:eq(0)"]

Unfortunately it doesn’t work the syntax for the selector seems not be correct! Someone could help me please? Thanks!