Crashes occur most often when I apply a highlight to text. I've had 3 crashes while highlighting text in the ESV, and 4 crashes while highlighting text in Douglas Moo's Pillar NT commentary on James.
Not every crash shows the "Accordance quit unexpectedly" dialog box -- sometimes Accordance hangs for a second or two (a "spinning pizza" shows up) and then silently vanishes.
I've now taken to saving (tedious as it is) a named session and regularly saving (overwriting the same session file) so that Accordance remembers where I was, etc... otherwise after reopening after a crash the session is not properly restored.
Not sure if it's any help but I've attached the crash report (from a recent crash that occurred while highlighting).
I cannot recall exactly when this started, but I think it was either after upgrading to v9.5.6 or v9.5.7.