Scott: Yamaha's Open Plug-in Technology or OPT panels are control panels and/or voice editors that work within other programs like Sonar 2.0. To my knowledge, the only OPT panels Yamaha has released so far are for the Motif and the Tyros (the stand-alone voice and file management programs that ship with the Tyros are also OPT panels). This allows you to open a voice editor from within Sonar 2.0 instead of having to use a completely seperate voice-editing program. As Yamaha says: "so you don’t have to open up a second application, “ALT+TAB” between programs, or tie yourself in knots with multiclient MIDI links". Yamaha tried this idea with their own XGWorks program and the plug-in voice editors that came with their PLG-family of expansion cards, but with the demise of XGWorks Yamaha has wisely chosen to create a technology that allows their exclusive voice editors to run within other popular programs. I am very hopeful that Yamaha will convert the expansion board plug-in programs to OPT and produce an XG OPT panel sometime soon. Yamaha has more info on OPT here:
http://www.yamahasynth.com/pro/opt/index.html