How do I export from FCP to a QuickTime file with multiple audio channels?

Question

I'm delivering a project where the first step is to generate an HD Cam SR master, which I will be doing at a post-production lab. They will then do a QC check for me. To generate this HD Cam SR master, they need to me to bring in my 98-minute long movie on a firewire hard drive, in five equal parts -- QuickTime files. From these five QT files, the lab will then be creating an HD Cam SR master that will have...
dialogue on tracks 1 and 2
effects on tracks 3 and 4
music on tracks 5 and 6
MY QUESTION
a) I don't see any way to separate these audio tracks accordingly in the FCP menu for QuickTime export. Does anyone have any experience doing this?
b) And does anyone know the most efficient way to combine timeline audio tracks for this purpose? I have my dialogue sitting on the first FOUR audio tracks, actually. To deliver this film, I'll need to crush these four audio tracks to two, as listed above. I could generate an AIFF file, I suppose, import it back onto the timeline, sync it up, and then re-export along with the visuals to make the final QT file, but this seems like a generation loss.
thanks,
Shanked
PS the movie is made up of footage from a Sony PMW EX1. I used the codec "XDCAM 1080 24p 35mbs VBR" for editing in FCP. I'll either export to QT using this same codec or switch to "Apple ProRes" if my machine can somehow maintain the sync.

Answer 1

The following will answer both your questions a) and b).
Click on your master timeline and press cmd+0 (zero) to bring up Sequence Settings, then click on the Audio Outputs tab on the right. Click on the Outputs option and change it to 6. You can leave them as Stereo pairs.
Now, back on your timeline, you need to make sure all your audio is organised so each track. A1, A2, A3, A4 etc has all the relevant media on it.
Then, on the left of the timeline you see the Destination toggle buttons, then you see the Padlocks to lock tracks, then you have the Toggle Auto Select squares. If you right-click on the Toggle Auto Select squares you bring up a little sub-menu, at the top of this list you'll see Audio Outputs, which will show the stereo channels for that particular track. As you've changed the number of Audio Outputs in the Sequence Settings, the list will show: 1&2, 3&4, 5&6. You just tick whichever channels you want.
In your case, you have dialogue on the first 4 tracks, no problem, just go down through tracks 1,2,3 and 4 as described above and assign these to Audio Outputs 1&2.
Then just go down through your music and effects audio tracks and assign them accordingly.
Now, when you export your timeline as a self-contained media file, it will have different audio channels.
I hope that makes sense. When you change the number of audio outputs as described in the first step, I believe the rest of it is fairly self explanatory, once you know where the settings are.