I sent an email to tech support, but thought someone might have the answer to what went wrong. I tried starting with the ctrl key twice without any success, saw errors in the two log files but, didn't fully understand what they meant. L5 worked while indexing was in progress, shut L5 down while "first time indexing" was in progress (which finished successfully), then after which L5 repeatedly crashed.
5100.Logos log 7_28_13.zip