Cubase10 crashing when attempting Arranger track flattening! 
(cubase 10.0.40 on Windows10)
it produced an error message saying the usual “A serious error happened, save your project with a new name and restart the program”, etc…
I was able to save even though it didn’t show the “flattened” result of the operation. It crashed (disappeared totally) just as I clicked save. However, to my surprise, after I restarted the program, the saved version was there and I loaded it. To my even greater surprise the project now showed the flattened arrangement complete tracks and it played without problems. I repeated the flattening operation in other different new projects and it all happened again exactly as described above… 
Hi,
Could you attach the crash dump file, please?
Thanks for your reply, here’s the crash dump file:
Cubase Artist 10.0.40.284 64bit 2019.11.4 15.53.29.495.dmp (770 KB)