The best method to test you site is to download a utility called MAMP which gives you the latest versions of Apache web server, PHP and MySQL. This is a free download if you search the internet. Follow the download and installation instructions.
Under the Site Setup pane in RapidWeaver, enter the following URL in the Website Address box: http://mysql-host:8888/

When you export your site, save it as
htdocs and set the export path as /Applications/MAMP/

When the export has completed, open your web browser and enter the address http://mysql-host:8888 in the address bar. When you view your site, it will behave exactly as it would on a real web server the public have access to. So scripts will run properly and code such as PHP will be rendered correctly. MAMP has a dashboard widget available and a utility so that you can switch your personal web server on or off and configure it.