Widgets and Themes customization does not work

Hello everyone,

The problem started when I updated from 3.4 to 3.4.1 multisite install,
few things stopped working.

When I run wp-admin/customize.php I get a blank page with the menu on the
left. I tried changing to Twenty Eleven and it does not
work with any theme.
Also the widgets no longer work/display with any theme selected, including
Twenty Eleven.

We did not have this problem up until the 3.4.1 come out.
I am using the Super Admin credentials.
Did not work with google chrome or IE9.

Is this a bug or some files got damaged?

Thanks
Davys