Hi!
I am not sure if you have done this yet, but your store categories need to be updated from Ebay to Auctiva. Go up to the "My Account" tab in Auctiva, click on the "Settings" tab and then "Ebay Settings". On that screen you will see a link to "Update your Ebay Store Categories".
Once that is done, you will see a pull down bar with your store categories in your listings.
Hope that helps!
Marcia