First, please make sure you are using b9 of both Live and Max.
When Live calls the Max app to start for the first time, we need to copy all the frameworks from the Max app over into the Live app. Sometimes permissions problems prevent this, an issue we hope to address in a future release.
For now, control click on the MaxMSP app and select "show package contents". Navigate to inside the Frameworks folder and copy the four frameworks folders you find there.
Now control click on your Live b9 app and select "show package contents". Paste the contents into the Frameworks folder you find inside there in the Contents folder. If there isn’t one, please create it first.
If it still doesn’t work, please get in touch with cycling74 support.
Please note that we are monitoring this list and the Ableton forum so you shouldn’t need to cross-post.