I have been having some problems with Quicksilver crashing. Not very often, but since I prefer to run it without an icon in the Dock or the menu, it's quite annoying when I try to use it the next time. To solve this problem, I decided to use launchd and its ability to react on the change of a file, namely the crashlog for Quicksilver.
I prefer to use Lingon to manipulate the launchd, but here's an example plist as well. In Lingon, use the Assistant and select "Run an application/script when a file is modified." Add a suitable Label and in the last step, use the Path buttons to select the program you would like to restart and its crashlog. Press Create and you should have a working LaunchAgent.
If you don't want to use Lingon, paste that plist into a text editor. Change the WatchPaths and ProgramArguments to fit your system, save the file in ~/Library/LaunchAgents, and name it something like nu.wallner.QuicksilverWatch.plist. Load it with this command in Terminal:
launchctl load ~/Library/LaunchAgents/nu.wallner.QuicksilverWatch.plist
Hope this helps you as it has helped me!
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