I'd suggest just breaking your problems down into simpler tasks. For example, in your other posts, it sounds like you have a kind of complicated setup, and are not explaining yourself very well.
Try this - instead of trying to get everything setup the way you imagine it should be, start simple. Before you get to midi, just see if you can get an audio track with some imported audio to play correctly. Ok that works, now see what it'll take to record your own audio. Just a simple computer mic saying hello world. Now that works. Now try creating a midi track and just drawing a bar or two of midi notes, and fire some built in soft synth with it. Then see if you can fire an external device like your mpc, etc etc.
Anyway, my point is, keep it simple and master the basics first. And read your sequencers manual as well.