I'll give you as much information as I can. I play live in 3 bands/projects: Cyclic Vendetta (post hardcore metal), X1stance (synthpop / electronic rock), Encoder Logic (electronic). I use the same basic setup for live performance on all 3. I play the backing tracks from Windows Media Player or Foobar2000. I have a Kurzweil PC3 keyboard that I use mainly as my controller, connected via USB to my laptop. Sound comes out of the laptop from my M-Audio Micro interface (they don't make them anymore sadly). With Cyclic Vendetta, I also take audio input from my keyboard and send it through Buzz and out through the interface. I just have to design my splits carefully with some of the split programmed in on the keyboard and some of it programmed in Buzz. On to splits: I use 3 things right now for splits. First is the easiest: IXSplit, since you can graphically design your splits it makes it easier. However, it doesn't have pitch bend, aftertouch or mod wheel and I sometimes need those things. So in those cases, I set the range manually in the Polac VSTi settings for each part. Yes it is more time consuming, but still way easier that doing the same thing on my Kurzweil. The other kind of split I use is built in to the Jeskola XS-1. It is really useful for designing multi-layered orchestral patches (up to 16 layers). You need to select your MIDI channel in the interface for each layer. Speaking of MIDI channels, I use usually 1 channel per song (although sometimes I change channels mid song). So for each song I'll have my keyboard split, and it will be set on a MIDI channel. I keep a set list in the "blah blah" section (Info View is the technical name although I've never called it that) of Buzz, so that I can keep track of key signatures and which instruments I'm playing on that song. Something I put in the "blah blah" section is a big warning message that says "DON'T FORGET TO LOCK TO MASTER". If you don't lock the MIDI to something like Master that doesn't take any MIDI signals, if you accidentally click on a VST or Buzz instrument it will play the instrument that has focus, and the instrument that is assigned to the MIDI channel you are on (I think this only affects MIDI channel 1, but it's really annoying when it happens. I group each MIDI channel into a MixIO and then each MixIO into another MixIO and then send that through a Jeskola Limiter. I like Jeskola Limiter because it's light on the CPU, has no detectable latency, and sounds good.
Here's a project file from my latest show that should help explain visually:
https://www.dropbox.com/s/fsdndwwb0bc0g ... 7.bmx?dl=0
I end up using mostly VSTs, but definitely nothing against the Buzz gens, especially Infector and Qsamo which are 2 of my favorite synths.
Hope that helps. Let me know if you have any questions.
Edit: One of the things about IXSplit is that you need to have enough tracks for the polyphony you need. So if you need 10 note polyphony, you need 10 tracks. Also, if you are doing layered tracks on the same instrument (e.g. octaves), you need to set the mode to "Matched" and set the base track of each so that they don't conflict with each other. So add more tracks, set each zone to "Matched", and use a different offset for each.
Thanks a lot.
... there is a midi-learn function in Polac-VST-Loader, so assigning the knobs really isn't difficult ... .