Control Surface for Sonar with TouchOsc How to get feedback?

I am using AC-7 in the iPad to control Sonar, but I do not quite like it, with its tiny buttons and all. I got TouchOsc recently and I was thinking about creating a clearer, tabbed layout that works as ACT controller, too. It does not seem difficult to make it work unidirectionally, but I have no idea about getting feedback from Sonar. I see that AC-7, working like a Mackie Control, is updating track labels, faders and meters, but i don't know how. Since midi is being used, I guess that it is done with sysex, but i cannot find any info about how to set up something like this.
 
Anyone can help? Thanks in advance,
 
Jose.