[NB. I believe the following may apply to Toast 10 as well]
MacBook Pro (early 2011); Snow Leopard 10.6.8; 4GB RAM
Around September 2012, Toast 10 (most current version at that time) suddenly began crashing on me, usually just at the point when I clicked Burn on an Audio CD. Soon it would crash on launch.
I tried the strategies recommended on this Roxio help article.
None made any difference.
Come November 2011, I took a gamble and upgraded to Toast 11, thinking this might solve my problem. It didn't. I couldn't get the the app to last past a brief glimpse of the Setup Assistant screen. Having forked out a bit of cash (to no benefit!) I was motivated to go back and try solve the problem by a process of elimination. (Yes, I should have done that in that first place.)
Based on something I'd noticed in the crash report, I decided to quit or turn off all my log-in items (Growl, QuickSilver, Dropbox, Breeze, and so on), most of which live in my menu bar and do stuff in the background. This fixed the problem! I was able to complete the setup process and then make an audio CD project and burn it to disc.
When I restarted and allowed all those tools to load as normal, Toast began crashing on launch again. So then it was a process of narrowing down which of the tools was a problem. I finally identified it in an app called Timing. This app operates in the background, tracking what you're doing, basically a local version of apps like Slife and RescueTime. It was after I'd purchased and installed Timing that Toast began crashing.
[blue sentence has been edited since original post.] I want to add here that the developer of Timing was very responsive and came back promptly with some suggestions that involved disabling AppleScript tracking in the troubleshooting pane of the Timing app preferences. I ended up deciding to stop using Timing for other reasons, but the point remains, that failures in Toast may well be the result of a conflict with another app. So if you're also experiencing the crash-on-launch problem, take a look at what's running in the background, especially on the third-party front.
So I'm pleased to have solved the problem, but also kicking myself that I didn't go through this process with Toast 10, which was adequate to my needs - I could have saved myself a hundred bucks!