Why do FinCEN reps give advice contradictory to the written instructions?
My experience is that they only do that when 1) they have not read the instructions and 2) have no personal familiarity with the report at all.
Include all current addresses you have; residence, P.O. Box, the lake house, etc. using the (+) thingie. Ambiguity exists regarding "previous" addresses: I vote "No." Putting
anything into the narrative instead of a "text box" that requests that information makes it harder for law enforcement to find and link to reports listing the same information.
As for a non U.S. person, if they signed a W8-BEN or its equivalent, gave you a U.S. address and a non U.S. address. Report both.