If you look at the bottom of the screen on the right hand side, you will see three buttons. I wasn't sure what they were at first, so I played around with them. The first one will allow you to choose the "free style" "auto mode". The middle one will let you change the border color, wights, and corner style. It will also allow you to change the shadow of the frames, and it has a simple image effects. The last one is all about background stuff.
So after playing around with colors, shadows, and image effects, I decided on a color I wanted for the frames, but didn't care for the background. So, I clicked the third button to change the background.
Disclaimer: Even though PearMountain Technology provided me with a copy of CollageIt 3 Pro free of charge, the words in this post are that of my own.
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