Complex sentence: Napoleon remarked to Antonio Canova that its lack in the museum he accumulated in Paris was the most important gap in the collection, and the sculpture was more than once crated ready for shipment to Paris before the Napoleonic regime fled Naples.
Split into simpler sentences: Napoleon remarked to Antonio Canova that its omission from the museum he accumulated in Paris was the most important gap in the collection. More than once, the sculpture was crated and made ready for shipment to Paris before the Napoleonic regime fled Naples.