Hi Kevin. You have to overlap* notes when you're using VSL legato (and portamento) patches or else the legato transitions won't happen. (The VI "sees" the overlap and selects the correct legato sample.) Don't pick up your fingers between each note and you'll hear the proper effect. After you've recorded a legato line, look at the notes in your sequencers' graphic editor and make sure each one overlaps with its predecessor.
(* Or at least make sure the gap between them is no longer than 50 milliseconds!)