ISSUE IS FIXED for me. After downloading a patch, error, closing Cryptic launcher, repeat, there was one massive update (few gigabytes) it started to work. No more: quit unexpectedly error. Note, it took 4 or 5 updates.
Same error here. Client Quit Unexpectedly. Opened a ticket with Arc support earlier today, they replied: " (...) To increase visibility for the issue, or to see if other users found a workaround, we'd recommend posting about this issue on the official bug reports forum (...)" Therefore, here I am.