Hi, I had the same problem..
My site was took down.. so i asked my server to get the bakcup of an hour ago back.. so my site was ok again.
After that, to be more carefull, i used my dev site (staging site) to update the plugin 1 by 1… it was 21 plugins requesting updates..
So i started updating 1 by 1.. after 10 updates.. i got to the Flexible Shipping Update.. and voilá..it broke down my site (staging site at least)
How can i produce the log error so I can send it to you?