When dualcore support is ON, Ableton crashes when loading a track. It loads all instruments, the cursor (Windows) changes to an hourglass and it immediately afterwards crashes.
I only get a Windows crashbox, nothing from Ableton itself. I can't find any crashlogs and also the regular logs don't show up anything noteworthy.
When I turn dualcore support off, I can load tracks and then have to turn it on again to benefit from two processors. However, every now and then it will crash when adding a EVEN NATIVE effect.
The whole reason I wanted Live 6 *was* dualcore support. I have sent in crashlogs and bugreports from 6.0.1 and subsequent beta versions but I don't hear sh*t from support.
To be fair, i did get one mail in october, to say that since it was so early after the version 6 release that they had a lot of support events to deal with.
I was cool with that, but it's been months and we're at 6.0.3 and STILL it feels like something that shouldn't be out here as a finished product.

There's a fine line between disappointment and anger... I can't really tell which I'm feeling at the moment.
(For those that are still reading: I'm on a Windows machine, it's used ONLY as a musical platform, my main computer is an iMac downstairs. I have a dualcore P940 (3,4 GHz) and 3 gigabytes of RAM, I use an ESI ESP1010 as my soundcard all the latest drivers etc. etc.)
Well, I'm off to reboot since every Ableton crash messes up my ASIO-drivers. I can work around the crashes somewhat by not enabling dualcore, but djeez... it's such a waste of time...