well I guess if we are clear on what your trying to do we can respond.
If your trying to process images via a url you need to point to an html page which has img tags with full urls to images and we will try and strip images out of the page we can find. Thats probally why you only get certain images pulled as those are the only ones found. As far as bulkuploading and processing files via a server path you must place the proper server path to a directory on your server and make sure that path is 777 permissions and hit the skip upload box
So really its all in what your doing.