Using thumbgen and movie thumbnailer

Is there a way to create only thumbnails for video files? I have trying to use thumbgen to create just the thumbnail for certain videos and have it setup to use movie thumbnailer to create them but for some reason they still don’t show when i view them on the hub. I have a folder thumb but can’t figure out how to get thumbnails for the videos to show. ’

Sorry if that made no sense …

make sure the image is same name as movie file and xml. and make sure its jpg