Re: nearly the same issue
I run Vista Pro 32-bit, even with only 1 session open if I wait a while WinSCP will freeze (have now had it happen 30+ times, even after a reboot).
Can you send me an email, so I can send you back a debug version of WinSCP to track the problem? You will find my address (if you log in) in my forum profile. Please include link back to this topic. Thanks.