Only 2 minor tweaks:

1. increased fastcgi_read_timeout to 120. unpacking files took longer than the default value.
2. added a rewrite rule since I'm not using Apache (who in their right mind would use it anyway ?:):

    if (!-e $request_filename)
    {
        rewrite ^/(.*)$ /index.php?/$1 break;
        break;
    }

Update (build 75) downloaded fine.