The Auctiva store and the eBay store are completely separate store fronts. Your Auctiva store is a collection of all your active listings (auctions, fixed price, and store), that can be reached by clicking the "Click here to browse all my eBay items" link on the bottom right of the store window.
An eBay store is still needed if you wish to list eBay store items and take advantage of the longer durations and smaller listing fees.
The Auctiva store format cannot be applied to your eBay store.
For further assistance with this matter, please file a support request regarding this issue using the appropriate link on our help page: