Wow, first crash I've had in ages. I had just done an Expand Stroke then clicked on divide and AD was instantly gone. Attached is the crash report. AD beta 1.9.0.6 on a mac running Sierra in separate mode.
FYI when I reopened the beta I wasn't offered to open the recovery file. A blank canvas was what I got, then when I told it to open the last saved it then offered the recovery file. I don't know if the offer was just slow or if it wasn't triggered until I tried to open the last saved.
When I redid the expand stroke and divide it crashed again. I tried to upload my .afdesign file but after it did I got an error message saying -200, twice.
Crash 11-9-20.txt Crash 11-9-20 second.txt