Download Lock Module and Amazon s3

I currently have Robin’s Download Lock module working on my site. However, I would like to try to move some of the media to Amazon s3. I can link to the file when it is on s3, but the Download Lock module throws this error:

Notice: Undefined property: Download_lock::$download_path in /xxxx/public_html/xxxx/modules/download_lock/mod.download_lock.php on line 172

Can someone give me some direction with this?

Thanks Much,

Jesse