Hi friend !
I understand the frustration but that error has nothing to do with the update . I made the update in the middle of a few cd productions in progress so i took the risk . For my surprise everything went very smooth . I keep working on it everyday since we got it and it feel real solid . Btw i didnt trashed prefereces neither .
That access violation error happens because a lot of things .
So its maybe time to start troubleshooting
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I see you have Mac and Pc on your profile . Can you give some information about your configuration so all here can help you better ?