Just got my copy of GPO. Talk about user friendly! But - when trying to set up sostenuto in "Options" I can't get it to work. Sustain works properly but when set to sostenuto there is no effect whatsoever.
I am using a Kurzweil PC-1X keyboard through a Tascam FW 1884 control surface (my midi port) to my PC. Using GPO as VST in Cubase SX 2.