problem when transfering files

Sometimes when you transfer big files,3-10 MB from local computer to remote computer,via SFTP , after you drag and drop the file on remote computer if you click cancel very fast it will not say nothing and you need to click again or it will disconnect you from remote computer ,i have seen this on older versions too ..not only the latest had problem,i had same problem on Windows XP Pro SP2,Windows Home Edition SP2,Windows Xp Service Pack 3 i`m using right now,same problem,it's clearly a bug.

Please check this problem out,it's critical.

I have sent you a debug version.