This new feature hasn't made much of a fanfare re the new release but I believe it's a great improvement. At last you can have meaningful image names rather than Xara's previously random generated and constantly changing image filenames.

Image filenames

You can now control the filename with which any image is published in a website or web document, which can help SEO and your position in image search. Select the object and open Utilities > Web Properties > Image tab. In the Image section of the dialog you can set the preferred filename to be used. If the filename is not unique within the current website/document, Designer will append a number to the name to make it unique.
I haven't had enough time to check yet but I believe this will also eradicate the BIG issue with using the previous 'filename=image" naming convention that led to issues between variant image quality.

So in my opinion the Developers deserve a big pat on the back. Thanks Dev's.