I have experienced similar vexing issue since my upgrade to Accordance 10 this summer. I do rather elaborate highlighting of the DSSB text in parallel with MT and Accordance increasingly crashes, sometimes with the message
Memory error #-109 in procedure "OTChangeHandle"!
I use two machines, both of which sync with Dropbox and the crash has happened on more than one occasion on both. Once this happens, Accordance will not successfully reopen whether I choose to recover my last session or not. I normally can go to Library > Preferences > Accordance Preferences, rename the General file, and start over (requiring that I re-enter my name, affiliation, and start up preferences) AND, via Dropbox, choose an earlier version of my highlight file (meaning I will have lost some of the more recent highlights), but this does not always work (on one occasion on one of my computers Accordance would not start without crashing even though I had renamed the general file; I ended up reinstalling). The problem is that one or both computers are now rather regularly crashing while I highlight (once a day or so) so that I am somewhat afraid to use the program for fear of having to waste time re-highlighting and re-starting Accordance.
Hoping that you can soon resolve this troublesome issue,