To create your own scrolling affirmations for Zen mode and custom startup splash image. Instructions for custom affirmations. Go to Bejeweled 3 Affirmations folder (In XP, it's probably C:\Program Files\Bejeweled 3\affirmations). Copy the one you want to edit to desktop. Edit it to say whatever you want and save it. Copy it back, and confirm the overwrite.
For a custom Splash, go to the Bejeweled 3 Properties folder (In XP, it's probably C:\Program files\Bejeweled 3\properties). Copy partner_logo.jpg to desktop. Edit to whatever you want then save. Copy saved partner_logo.jpg back to properties folder.