Can't buy photos in Smart Galleries

All my public galleries were smart galleries that consisted of photos that came from password protected galleries. This appeared to be working fine again, except that visitors cannot purchase the photos. If they click Add to Cart on one of these photos, they get a message "Wrong Permissions" and cannot continue to the shopping cart. It works fine for photos that come from Unlisted galleries, so I've switched to that, but I think the problem with Password Protected photos needs to be fixed so people can purchase them if they see them in a Smart Gallery.