This was the last thing I wanted to use Apple Soundtrack for - to create music synchronized to a Quicktime video.
Now this is possible with Live and this tool
http://www.grantedsw.com/revision/
gfisch
LiveSecret 02: Synchronize QuickTime Videos
LiveSecret 02: Synchronize QuickTime Videos
G5 2x2 / HDSP 9632 / PowerCore / NMG2 / BlueSky MediaDesk 2.1
Live 4 / Faderfox LV1 / Virus PC / PPG Wave 2.V / Albino2 / Operator
MachFive / Athmosphere / Stylus RMX / Trilogy / Wired / Morphology
Ozone / Inflator / TransMod / Antares Filter
Live 4 / Faderfox LV1 / Virus PC / PPG Wave 2.V / Albino2 / Operator
MachFive / Athmosphere / Stylus RMX / Trilogy / Wired / Morphology
Ozone / Inflator / TransMod / Antares Filter