Probably not much help to you but quite honestly whilst Virtual Instruments work to some extent in a home studio, I don't believe using them in a live setting is a great idea. If you are looking for a specific sound it may be better to find a dedicated specialist module. For instance an XM2 if your after a Hammond Sound (or even an older XM1 will outperform any current Virtual Instrument) or Ketron Klavipro if your looking for Piano. If your after a quality general voice module, then Ketron SD2 or SD4 or Rolands SD20 might be worth a look, both can be connected to a laptop although the SD20 might be more difficult to use directly with your Yamaha.