If you want separate audio outs for the style generated parts, you are going to have to load a 'chord track' into a DAW, then feed that out to a Genos song channel.. And then assign that track as 'chord detect'. This way the Genos will read hour chord track (should be blocked organ type chords, full duration till next change) as if you were playing it with your left hand.
Make your DAW the MIDI master, and Genos mid slave, (like usb 1) Record your style changing performance into you DAW. It will be a midi track with Channels 9 - 16
The simplest way is to go to Genos SONG RECEIVE page, and assign SONG MIDI 9- 16 to their respective Style channels
MIDI 9 - rhythm 1
midi 10 - rhythm 2
midi 11 - bass
midi 12 - chord one
This will now feed the style generated parts to the style generator, so patches, and most importantly dip effects will be the same.
Since Genos has only 4 outputs, you can go back and record each audio track one at a time, into your DAW, and it will all be in sync. The nice part about this is you can, EQ, volume control, effect control with much more precision.
You should of course practice this at home, so you won't be overwhelmed when you get to studio.
If you want it to go fast, you can of course, just record the whole style generated part as a live two track. Then really focus on your lead playing, harmonies, etc.
It is quite versatile, although it takes some time to master.
There's a digital and analog out, but personally the fidelity is so good, I just stick with the analog out.
There is a wah-wah on Genos, its OK .. but it won't get as radical as Shaft sound. If your studio has a wah wah pedal, it might be more authentic, but this would mean using the first overdub method I suggested.
As mentioned Yamaha doesn't care how you use the styles, you just cannot bundle the styles, and sell them outright.
MIDI files found on internet, can be totally lousy to excellent. You need to preview the midi files you plan to use, Some may only be piano, and a lame repeated midi drum loop. Some are exquisitely arranged. . Yamaha's midi files are decent. It would be worth it to purchase any there as they will have more parts in them.
If you are not familiar with the Genos, it would behove you to figure out how it works.. If you can get ahold of a Tyros it's pretty close in function.. Nothing is as nerve-racking as trying to get something to work, with a $$$ clock running.
Hope this helps