I ran a remote sync command and it walked through comparing all the directories and then looked like it would start syncing.. but hangs... one note.. in the first dir there are over 10k image files.
C:\Program Files (x86)\WinSCP>WinSCP.com /log="C:\Users\SQLAdmin\Documents\winscp.log" /loglevel=2
winscp> open <<<ftp site>>>
Connecting to <<<ftp site>>> ...
Starting the session...
Active session:  <<<ftp site>>>
winscp> synchronize remote "D:\Images\Files" "/"
Local 'D:\Images\Files\z' => Remote '/z'
The tail of the log shows..
. 2015-11-18 14:08:20.238 Local file 'D:\Images\Files\z\ZT-Z34-3G-DFLY-RMR-DLC_1.jpg' [2015-10-19T19:53:41.000Z]  is new
. 2015-11-18 14:08:20.238 Local file 'D:\Images\Files\z\ZT-Z34-3G-DFLY-RMR-FDE_1.jpg' [2015-11-17T20:51:44.000Z]  is new
< 2015-11-18 14:08:20.769 Script: Synchronizing...
. 2015-11-18 14:08:20.769 Synchronizing local directory 'D:\Images\Files\' with remote directory '/', params = 0x2 (NoConfirmation)
. 2015-11-18 14:08:20.769 Synchronizing local directory 'D:\Images\Files\#\' with remote directory '/#/', params = 0x2 (NoConfirmation)
it has been there for hours..
I have connected to the site via Filezilla with the same credentials and manually moved a file to the folder to be sure it was not a permissions issue.
I have the latest version (downloaded today 11/18/2015)