auto thumb doesn´t work

I put:
[video_lightbox_vimeo5 video_id=XXXXXXX width=640 height=480 auto_thumb=”1.]
But there is no image and I get this message:
“Error! You must specify an anchor parameter if you are not using the auto_thumb option”

What´s wrong? Thank you.

http://wordpress.org/plugins/wp-video-lightbox/