Thumbnail confusion

There has been a lot written recently about pulling in thumbnail images for videos, and to be honest, I'm not sure what is what anymore.

I am using contemplate, and I have a field set up in CCK for the video, and another for the thumbnail. The video is configured as a file with no download link and the thumbnail image is set up as a thumbnail in the field configuration.

I am calling my contemplate code this way:

 if ($field_video_player[0][filepath]) {
print "Click play to watch the video below:";
 print swf(
 $node->field_video_player[0]['filepath'], 
 array(
 'flashvars' => array(
 'image' => ($node->field_video_thumbnail[0]['filename']),
 'params' => array('width' => '425', 'height' => '300'),
)
));
 }

No thumbnail is generated. I am wondering if I am doing this incorrectly in Beta5, or what they problem might be?