FormBuilder 0.82 from the guys at TruthMedia Internet Group is a great WordPress plugin. In my opinion its just as good if not better than the cForms II plugin from Delicious Days.
FormBuilder is a quick and simple way to add forms to your website and provides your website administrator the tools to manage form entries. You can even set the plugin to record form submissions in the database to be downloaded at your request to a nice clean CSV file.
The form submission data is stored in the MySQL database in an XML format to retain your custom data structure. However, here is the problem. Parsing the data through the export, from XML to CSV, can be exhaustive. I found that having any more than 2,000 submission records would cause timeout issues.
Even after altering the server configuration for Idle Timeout and memory allocation, I would still experience 500 Internal Server Errors. And so I decided to get my hands dirty and re-code the export class.
The i am root version of the export class can be downloaded here for free.
Simply uncompress the formbuilder_xml_db_results.class.php file and upload and overwrite to /wp-content/plugins/formbuilder/extensions/location/
Please make sure to do a full backup of your site and database before making the change.