You won't be able to dismiss this by usual means (escape or click button), but you can close it programatically based on user choices or actions.
"I used this item sort of backward and nontraditionally. I made my big invitation for the reception due to inviting everyone there. I wanted to keep the ceremony more private, so I chose to use this Details card as a private Ceremony invite for immediate family. Since I was only getting a small number, I rounded the corners. I chose to keep the background color on front and back. I replaced the white, blaze and baltic colors with bay and ivory on blaze background."
"Since my wedding ceremony will be taking place during a week-long Caribbean cruise, I purchased this enclosure card to communicate "Cruise Information" such as cruise booking #s, contact information, group flight confirmation #s, and additional general cruise details. I also included a link "for more information" to our wedding website. The flexibility of this enclosure card made it easier to convey a lot of extra, unique wedding information to my less "computer familiar" guests."