If you are interested in making a number of Themes I would suggest that you make a Theme called Template.zip


To create such a Theme go to Default

Type in you all your Custom Appearance Settings as well as your preferred back cell image.

The Theme you are in now will have become Default*

Rename default* as Template and Export.

That will give you a backup copy.

From the moment you have made Template, just enter Template, load in a new background, make any other changes you deem necessary, rename the Theme with rename and save.

This is very quick.