Happy update - I took it into Hexagon and the options for the sails were instantly visible - without even really knowing what I was doing, I was able to make each sail either set or furled, and import it into DAZ Studio.

I still want to see if I can make the sails 'work' within D|S, but this is enough to give me basic functionality - I can set sails as desired in Hexagon, and use the model thus configured.