Rikki's out of town,but I think she knows the answer,as she has OMB.
Personally, I use SGM180 soundfont and an Echo Indigo card,but I am GM oriented,not Yamaha as far as mapping is conscerned. On my pc, I have the Creative X-Fi. Excellent sound.
pa4X 76 ,Audya 76,Yamaha S970 , vArranger, Hammond SK1, Centerpoint Space Station