L4Mac took a while to start this morning ... that 'downloading and syncing' message, followed by 'preparing your library' message.
It crashed during this.
3716.Logging 1.zip
4810.Quit Unexpectedly - Apple Report 1.txt
I do not know if it was auto installing the new beta, so it may be a Beta 5 install, or a Beta 4 crash.
I started L4Mac again, to find the version and it crashed again ...
8713.Logging 2.zip
5037.Quit Unexpectedly - Apple Report 2.txt