Using the application LiveQuartz it possible to create a multi-layered collage from multiple images.

Creating Layers-
1. Drag & drop a photo file (.jpg, .gif, .bmp.....) into the canvas or into the layer list.
2. Uncheck the layer to hide the layer. Check the layer to show the layer.
3. Select the layer to work with it (click on it in the layer list).
4. The topmost layer in the list is the topmost layer on the canvas. Drag & drop layers to change the order.
5. Use the Alpha, Rotation, Scale, Zoom, and Filters tools to make adjustments to each layer.
6. Use the tools along the top for common photo editing tasks.
7. Go to http://www.rhapsoft.com/ for more information and tutorials.

Creating a Transparent Layer or Image-
1. Select the layer you would like to work with (click on it in the layer list).
2. Use the eraser tool or selection/lasso tool to delete the unwanted portion of the image.
3. You will notice that the layer is now transparent ("see through").
4. Save the file as a RHIF (LiveQuartz) file while working on the image.
5. In the version you export for use in other progrms, save as a .png, .tiff, .gif or .jp2 in order to retain the transparency.