How do enable style & Layout for Gravity forms ( Plugin)to work?

I have loaded the plugin many times and still get this displayed

# Internal Server Error

The server encountered an internal error or misconfiguration and was unable to complete your request.

Please contact the server administrator to inform of the time the error occurred and of anything you might have done that may have caused the error.

More information about this error may be available in the server error log.

Web Server at mdc24locksservice.co.uk
any adivice

I recommend contacting the author of that Styles & Layout plugin for assistance. We have no control over that.

Also, it will be important to get the actual error message from the server error log, or from the email that is sent to the site administrator by WordPress. Thank you.