I can't find any reference to an audio track limit on QT files. Doesn't mean there isn't one. What was the software that created the file?
If this is within your systems capabilities, copy the file, open it up in QT7, delete 2 audio channels, save it. Do that until it can be imported into FCP7 without crashing. I would even consider deleting all the audio and importing the video only to ensure that there isn't a problem with the video.
It's not a reference QT is it? just checking.
Curious, what are the track sources? 5.1, stereo, M&E and what else?
ak
Sleeplings, AWAKE!