To all:
I am a neophyte with Spark 2 and Spark LE, however, I have been able to accomplish this on my Win 7 64 bit system running both Sonar Platinum and Studio One Professional using Battery 4. The following are the easiest and most consistent steps that work for me and I hope this can help others.
1. Load both the Spark 2 and other drum software vsts. in my case, this is Battery 4. I will try it as well with AD2.
2. On Spark 2 make sure that under your preferences, you have checked both send midi from sequencer and send midi from pads so that they both say yes. You should see a checkmark in the box and then the word Yes next to it.
3. Open a new project in Spark 2 so that it is empty.
4. Change the midi imput of your drum software to Spark.
5. Arrange your drums to your liking. In Battery 4 I arrange the drum samples that I want into the row C3 which is already mapped to midi notes C3 through C4 so that it automatically matches with the spark le controller and I don't have to do the messy pad changes. If you want more samples than these 12 you can place them into the corresponding cells which are already mapped for C4 , C#4, D4 and D#4 to make full use of the two banks of midi pads on the spark LE, whichever is easiest for you and that makes it easy to keep straight in your head.
6. Now if you want to trigger the pads and hear the sounds on your drum software make sure that the focus of your DAW is on your drum software in my case,Battery 4.
7. If you want to use the sequencer of spark 2 with your drum software then do not use the stop, play and record buttons on spark 2 , you will hear nothing. You must then use the transport buttons on your DAW. You can then use the pads as well to record into your DAW. or export midi files from the patterns you have made from the spark 2 sequencer directly into your DAW directly into the track for you other drum software.
I have not yet fully explored all the connections, possibilities, and limitations yet, but it is a starting point. I hope this works for some of you. It is possible that other DAWs or Macs may not work well with this and having no experience with them I'm afraid I will be of little help in troubleshooting. Good Luck.
Dave