June 2018
just posting here to make this more visible.
have the same problem, also playing on mac, the exception raised crash appears at random times but it is persistent after the sunder mount quest. no way around it, have tried everything i found proposed by people with the same issue but nothing works.
also noticed that when this happens, one of the portraits of my crew appears bald and i know the save is corrupt. loading another area restores the hair on the portrait. would be hilarious if not so frustrating. this is a 2011 game, the loading times are like millisecs long and still won't run without game breaking bugs, it is quite unacceptable. i'm quite convinced that if the community won't find a way to deal with this bug, there simply isn't anyone in bioware in maintenance duty for a game this old, so we are pretty much f*****
also, maybe i'm just stupid, certainly tilted with this bug, but why cant i just find a way contact my problem with an email? why do i only get the option and would i want to chat about it?
November 2018
December 2018
I have some experience with Apple ruining software compatibility with OS updates. I tend not to play games on Mac, but I use it for work, and several times we've had to buy new software because whatever we were using was suddenly incompatible after an OS update. It's a bit of a PITA*.
(* pain in the neck)
December 2018
I had the same issue, tried all the fixes in this thread to no avail.
What worked for me: Open the Dragon Age 2 app from outside Origin.
Go to User >> Applications >> Dragon Age II (that's where my .app file is installed)
Open up your save at Sundermount and try to initiate the cutscene. Seems like this error is an issue with the Origin client.
Hopefully this works for other folks who are playing the game in 2018.