Results page blank

OK after some work I was able to get the results node to appear. It required an increase in memory to at least 64M, thanks to this node http://drupal.org/node/213435#comment-704884. But then the download node was giving a white screen of death (wsod). I was able to turn on errors by placing "ini_set('display_errors', 'On');" in my settings.php. This gave the error of "Fatal error: Maximum execution time of 30 seconds exceeded in ... sites\all\modules\webform\webform.module on line 1886". I gradually increased the execution time to 120 seconds and the download finally worked, by adding this "ini_set('max_execution_time', '120');". At this point, the survey had 4800 responses and 47000 rows in webforms_submitted_data.

My settings.php file now includes this for the webform module to work with a large number of submissions:

* PHP settings:
*
* To see what PHP settings are possible, including whether they can
* be set at runtime (ie., when ini_set() occurs), read the PHP
* documentation at http://www.php.net/manual/en/ini.php#ini.list
* and take a look at the .htaccess file to see which non-runtime
* settings are used there. Settings defined here should not be
* duplicated there so as to avoid conflict issues.
*/
ini_set('arg_separator.output', '&');
ini_set('magic_quotes_runtime', 0);
ini_set('magic_quotes_sybase', 0);
ini_set('session.cache_expire', 200000);
ini_set('session.cache_limiter', 'none');
ini_set('session.cookie_lifetime', 2000000);
ini_set('session.gc_maxlifetime', 200000);
ini_set('session.save_handler', 'user');
ini_set('session.use_only_cookies', 1);
ini_set('session.use_trans_sid', 0);
ini_set('url_rewriter.tags', '');
ini_set('memory_limit', '64M'); //added to allow numerous survey submissions in webform
ini_set('max_execution_time', '120'); //added to allow numerous survey submissions in webform

I can live with these changes but I hope this post will help someone else out if this happens.