To add new images all you need to do is locate the existing 'Backgrounds' folder.
If you accepted default installation settings then it will probably be here:
C:\Documents and Settings\All Users\Application Data\ZionWorx\2.6\Backgrounds
Then within this folder create a new folder to hold your new images:
C:\Documents and Settings\All Users\Application Data\ZionWorx\2.6\Backgrounds\MyPhotos
Now copy your JPEG or BMP image files into this folder.
When you start ZionWorx and go the Images tab, you should see a new category appear in the drop-down box named 'MyPhotos'. If you select this then you will see the thumbnails of your images ready for use.