Try this little utility that relies on HTTP headers to ensure your images can only be viewed from wherever you specify:
Enter the image url, location from where you want the images to be viewed, and the number of days before your image becomes unviewable. Click on Encode when you're done.
You will be presented with an encoded URL. Use this URL as a link to the image within Clubsnap. For example:
View Image Here
Try opening the URL from a new browser window. You should get an 'Unauthorized use of image' image.