That widget crash is problematic. It's something that I'm aware of and only affects the ICS scrolling widget. What's happening is that even though the task list is updating, the OS is not updating the widget views (this does appear to be a widespread problem according to stackoverflow.com). So, it crashes because it has one more view than tasks and it can't get to the task it wants to display.
I'm still trying to figure this out (I've got over 100 reports on this, but all of the developer suggestions I have received have done nothing so far). I've got another request for help out there. I'm just waiting for some help now.
I'll update the app with this fix as soon as it becomes available.