Hi you need to edit the saved listing on Auctiva with the correct template, copy the HTML code to your clipboard, open the active listing via your my ebay -> revise item and paste it in, however ..
The counter HTML is not included in the HTML to be pasted so if you want that retained (assuming it is there already) you will have to avoid overwriting it. A bit of confidence with HTML is required and certainly preview the result before commiting the change.