I was scrolling through one of my Notes files, in fact it was the one discussed in this thread:
http://community.logos.com/forums/p/362/140091.aspx#140091
I had imported it form Logos 3 (the .lbxnot file is in this thread) when Notes importing was first made available in L4. I was slowly scrolling through the file, letting each link highlight (turn color) so I knew that it was a valid link, since I had read that someone had found some broken links in their Note file (I had not). Twice, it just crashed as I was doing this,. A third time, I was able to go through the whole note file completely without it crashing.
Anyway, here is the log and crash file from the first crash. Hope it helps, let me know if you need anything else and hope you find the crash...
0284.Logos4.log
48664.Logos4Crash.txt