Blank Screen Even no Error in Logs V2.0.2 with PHP 5.4

Errors and warnings usually appear in ....\logs\php_error.log or ....\logs\apache_error.log depending on your php.ini settings.
Also useful errors are often directed to the browser, but as they are not valid html they are not displayed.
So "tail -f" your log files and when you get a blank screen use IEs "view" -> "source" menu options to view the raw output.