Error installing profile

First off I'd like to say how great the OpenChurch project looks!

I am having a problem running the installer on my web server. When I get to "Installing Profile" during the Drupal OpenChurch installation, I get the following message:

An AJAX HTTP error occurred. HTTP Result Code: 500 Debugging information follows. Path: http://mywebsite.org/install.php?profile=openchurch&locale=en&id=1&op=do StatusText: Internal Server Error ResponseText: 500 Internal Server Error Internal Server Error The server encountered an internal error or misconfiguration and was unable to complete your request. Please contact the server administrator, myemailaddress and inform them of the time the error occurred, and anything you might have done that may have caused the error. More information about this error may be available in the server error log. Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.

The server meets all of the system requirements for OpenChurch. I have read about PHP memory issues, so I looked into that and found that I have 256M.

I have no problem running the standard Drupal install - this only happens with OpenChurch.

Thank you for your time & help