Regarding your question “Could you be more specific when you say crashes? What happens, is there an error produced”:
The site this time went in maintenance mode when I update. Earlier attempts have just resulted in a blank screen with the name of the site on the top of the page. The first new update seemed to be working, except that I lost my sidebars.
I have tried my best resolving this issue myself, without success.
Hopefully you can work your way around this problem for me 🙂
Thankfully Petter