Perhaps I am misreading this code or this entire thread but you appear to be using the stor method

      stor ( FILE )
           Tell the server that you wish to store a file. "FILE" is th
+e name of the new file that should be created.
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Perhaps you should try the put method ?

       put ( LOCAL_FILE [, REMOTE_FILE ] )
           Put a file on the remote server. "LOCAL_FILE" may be a name
+ or a filehandle.  If "LOCAL_FILE" is a filehandle then "REMOTE_FILE"
+ must be specified. If
           "REMOTE_FILE" is not specified then the file will be stored
+ in the current directory with the same leafname as "LOCAL_FILE".

           Returns "REMOTE_FILE", or the generated remote filename if 
+"REMOTE_FILE" is not given.

           NOTE: If for some reason the transfer does not complete and
+ an error is returned then the contents that had been transfered will
+ not be remove automat‐
           ically.
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