It crashes for me too on Win 8.1 x64. I haven't been using the password storage due to lack of master password, so just did some quick testing.
I agree Otter is getting better and look forward to when I can use it for routine browsing. I just solved a couple of usage issues, and will figure out more the more I use it.
I found that the Fusion theme looked better than the system default (most/all others have too much white and flat look), but the icons on tab bar were too big. Moving tab bar to side and then back to top fixed that. The new tab and closed tabs ones are still maybe a tad large by comparison but the tab bar itself is back to normal.
I'm unable to get the lists that I selected in Blocked Elements to stay selected. Enable Content Blocking does stay checked but the individual lists do not. Some blocking is necessary for routine use. EasyList and EasyPrivacy, etc. are a good start, but custom filters are important too. EDIT: I was selecting the lists from the status bar button, which may be meant to be just for current tab. I've now set them in the Content Blocking ddialog from the Tools menu and will see if that sticks (now on 175).
What I'd really like is extension support, and not having to get them from google. Whatmight help until then are lists of user scripts we can add (is GreaseMonkey stuff supposed to work?). Most of the user scripting stuff seems to have about died out (too geeky).
It's working tonight. Best I can remember, there was no visible error, just spinning icon on blank page (indicating busy but taking too long to load). I have had some intermittent trouble with it over the past couple of months. (in USA.)
