Okay, I cannot seem to get portamento to work. I'm using Finale 2006 with the full version of GPO. Human Playback is enabled, and I'm using the glissando tool. In the HP options, I've selected the glissando/bend type to always use pitch bend (the other options just gliss chromatically, which is not the effect I'm going for). However, upon playback the strings just maintain the written note, then jump to the next note on the written beat.
I've tried using Controller 20, but have no luck their either.