Hi Barry,
First of all the TabStrip actually has nothing to do with MultiPage. They are often used together but there is no property on the MultiPage would change how the TabStrip looks and vice versa.
In order to change the TabStrip images, you would first want to know how those images are used. Usually TabStrip uses more images than any other controls. A TabStrip can use:
1. A left side image to create the left edge of the tab item;
2. A right image to create the right edge of the tab item;
3. A background image to create the background of the center part of the tab item;
4. The same set of images for hover state;
This topic explained how all these images come into play:
http://www.essentialobjects.com/ViewDoc.aspx?t=TabStrip%2fdesign_using_images.htmlGenerally, these images have nothing to do with localization. However, if you use image instead of text as tab item, then you will need to change TabItem.Image.Url.
Thanks