Why do you sign a msg. Not sure why to do this?

Ok, macs don't really get malware. unless specifically targeted for it. Macs are also very secure, and I really doubt you were hacked.

So question you locked your wallet, and then when you unlocked it crash, that means two things, one that your wallet was never unlocked. Which is the theory I am going with. I do think once you restored from a backup you should click new address and see if that address pops up. It also doesn't contain any fee so did you change your tx fee? I think this is just a freak thing and you have the address sitting your wallet. Unless did you run any java applications from the web, that is the only other way.

Also use -rescan, that will help a lot as well.

Thank you so much for this great tutorial, very good post.