There is a place in Brodgar, when you walk through the southgate, and come close to the first banner, that crashes the client everytime.
edit: actually it looks like its a whole line which is bugged. I swam around the western river and walked north when the client crashed again.
edit2: Ok i narrowed the error down to a crossraod being in sight, when he tries to load the ressource for it. And the reason for the crash is my systemclock, i changed it to 2003 to start an old program and forgot to change it back.