Regarding the problem of file timestamp after put operation ; properties of original file are:
created : June 24, 2005 9:00
modified : June 24 2005, 9:33
accessed : June 24 2005, 9:33
Properties of uploaded file:
created :July 14,1970 8:20
modified February 20, 1970 5:50
accessed June 24, 2005 9:33

Changing the option you suggests doesn't take any effects. Thanks you in advance!