Adding Color to a Frame
The Image editor allows you to add color to the background of a frame. This effect to add a color-wash to an image, or to fill an empty frames with color.

To set the background color for a frame, select one or more frames to reveal the Image Toolbox. Click on the 'Image' control to open the Image Editor.

Drag the Background Fill / Opacity control to the right to make the color overlay visible. If you drag it completely to the right, the frame background will be 100% tinted. If you drag it anywhere in the middle, it will be more or less translucent.
 

Adjust the Red/Green/Blue (RGB) values for the background fill, OR click the color tile to open the color editor:
 

Here is an example of applying different colors and opacities to a frame background will do to an image.

Next is an example of a basic collage that has used empty frames (no images) with opaque background color to decorate the canvas.

Be sure to uncheck the "Show Drop Image Here" box at the bottom of the Image Editor.

Adding a Background Tile to a Frame

You can use a tile within a frame background or blend it with an image in a frame.
FotoFusion comes with a selection of preset tiles; you can add your own jpg files to the C:\Program Files\LumaPix\FotoFusion V4\Tiles folder, then tag them in the Categories option of the Organizer to make them accessible when Searching and in the Image Editor.

Tiles can be used to create texture in empty (image-free) frames, such as in the example below.
Be sure to uncheck the "Show Drop Photo Here when Empty" box.
Here is an example -- two frames with background textures have been used to showcase an image.

You can also apply a background texture to an image, reducing its opacity to allow both the image and the texture to be seen simultaneously.

In this example, the two background textures from the previous example have been applied to images at a reduced opacity: