I transferred a file from one server to the other using two separate windows of WinSCP 3.7.4 (on Win7, SP1, 64-bit) and had the "disconnect when operation finishes" option checked. This worked as expected but then the second/receiving WinSCP instance complained about the transferred file missing from the temp directory. Apparently, WinSCP removes it's temp files on shutdown, which is basically a good thing, but here it causes a problem.
As a workaround I cannot use the disconnect feature, though it would be nice if this could be changed if possible.
PS: Copyright in the about dialog still shows the year 2005.
PPS: The subject field could be bigger for better descriptions