The most important aspect of the Client Response Gallery, proper setup of the Contact Form is essential. After all, client proofing and feedback is useless if you never receive the message. This setup is located in the Color Palette control pane.
Absolutely essential, make sure your Receiving Email Address is set correctly. This is the address to which galleries will send messages.
Optionally, fill in a 'FROM' Email Address. This address is only used to verify outgoing messages to your domain's mail server, therefore the address should match your domain. For example, my domain is theturninggate.net, therefore I should use an @theturninggate.net email address here.
Always test your contact form and verify that you are receiving messages from the gallery before sending the gallery to a client.