None of the SmartShapes have such a dialog.
You are supported to use the provide control to then tweak spacing.
I dare say there is a Registry setting for Xara's default.
I would prefer an input box somewhere for any given Duplication or even have Copy (A Duplication Selection) --> Paste Attributes (Another Duplication Selection) but Paste Attributes does not have a Duplication Spacing Attribute.
Acorn
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