Rikki, you are way ahead of me.....and I can't help but feel abandoned in my soft synth world.

Yes, you can use your SD1 to play lead or melody voices while using it to play the SD1 styles at the same time. All you need to do is set up the Channels you wish to use for this purpose and load in the appropriate instruments in kontakt and away you go. If you are going to use very high quality instruments then keep in mind it takes some 30 seconds or so to load a 2 GB Piano, etc. In a case like this you would preload such instruments in the channels of your choice and then change channels on your SD1 to call them up and play....instantly. As another alternative you could set up a multi in kontakt and then use program change numbers to call up the instruments you require. This may work best in your example of using the SD1 for both purposes (auto accompaniment and soft synth lead voices). Again you would preload all the instruments you require.

Rikki I trust you know that you can use Sonar or Cubase to play drum loops in sync with other things. I haven't checked but there could be VST instruments which may do the same thing....worth a check.