This has happened twice. While I was reading "Mastering Pastoral Counseling" in a floating window with the highlighter panel also in a floating window. No warning or message, windows simply crashed - not just logos but windows XP as well. 
I run on an iMAC i7 27" using Parallels 5.0 and Windows XP/ SP3.  
I am not sure at this point if it is the floating highlighter, or the new release of LOGOS.  (Slightly less likely is the recent upgrade to parallels.  I will try on another machine later to see what is happening.  It does not seem to happen if the hi-liter  window is not floating.  I can insert high-lighitng in the document without the crash if the high-lighter window is docked.