no details because it was one of those "crash without coredumps"... the only trace of the crash is this message in syslog:
10/6/13 3:13:40.556 PM com.apple.launchd.peruser.501[349]: ([0x0-0x6ad6ad].com.pleiades-astrophoto.PixInsight[6952]) Exited with code: 255
the crash had something to do with going back and forth in the history. i had an image with a big black border, so to look at the histogram properly i made a preview over the center area and told HT to track the preview. of course when undoing the preview went away, so i made another preview (which had the same name). i guess since the two preview objects are different objects despite having the same name, the histogram viewer would lose track of it. i went back and forth like this a few times, recreating the preview, but then i realized i should create the preview 2 steps back...
so i backed up two history steps and made the preview there. when i tried to select the preview in HistogramTransformation, i got the "Critical segmentation error catched" dialog and when i said "OK" to that, PI crashed with no log.
i assume this has to do with the different preview objects getting created and destroyed. i have not yet tried to reproduce it but i will. i still have all the *swp files if those are interesting at all.
rob