Using DW CS6, when at Manage Sites --> click on Import BC Site the login box apears and disappears quickly before I can put my credentials in.
I checked for updates and it is all up to date.
Can you see if this thread helps? http://forums.adobe.com/message/5125403#5125403
It's not resolved publicly on the thread yet. But if you think this is the scenario you're facing, I'll ask someone from DW team to contact you as well.
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